Semiconductor device having temperature sensor circuits

ABSTRACT

A semiconductor device that may include at least one temperature sensing circuit is disclosed. The temperature sensing circuits may be used to control various operating parameters to improve the operation of the semiconductor device over a wide temperature range. In this way, operating specifications of a semiconductor device at worst case temperatures may be met without compromising performance at other operating temperatures. The temperature sensing circuit may provide a plurality of temperature ranges for setting the operational parameters. Each temperature range can include a temperature range upper limit value and a temperature range lower limit value and adjacent temperature ranges may overlap. The temperature ranges may be set in accordance with a count value that can incrementally change in response to the at least one temperature sensing circuit.

This application claims the benefit of U.S. Provisional PatentApplication Ser. No. 61/971,702, filed Mar. 28, 2014, the contents ofwhich are incorporated by reference herein.

TECHNICAL FIELD

The present invention relates generally to a semiconductor device, andmore particularly to a semiconductor device including temperaturesensing circuits that provide operating parameter selection.

BACKGROUND OF THE INVENTION

Semiconductor devices include components that have characteristics thatvary with respect to temperature. For example, as temperature increasesmobility of charge carriers decrease causing transistors, such asinsulated gate field effect transistors (IGFET) to have lower drivecurrent. Although drive current decreases, leakage current (leakagecurrent when the IGFET is turned off) increases. These temperaturedependent characteristics can make design problematic.

When designing a semiconductor device, the designer will design circuittiming and internally regulated power supply voltages for worst casecorners. Typically, a fast corner may be high voltage, low temperatureand a slow corner may be low voltage and high temperature. By designingcircuits in a semiconductor device for a worst case temperature, powermay be unnecessarily wasted at another temperature point. For example, apower supply may provide a voltage that is unnecessarily high at a firsttemperature point due to the necessity of ensuring specifications aremet at a second temperature point, even though the semiconductor devicerarely operates at the second temperature point. This can cause power tobe wasted at the first temperature point, which is where thesemiconductor device typically operates.

A specific example is an internal refresh operation in a dynamic randomaccess memory (DRAM). At a low temperature, charge on a DRAM capacitorin a DRAM memory cell may degrade more slowly than at high temperature.However, to ensure specifications are met, the frequency of refreshoperations may be unnecessarily high at low temperatures to ensure thehigh temperature case is met. This can cause unnecessary powerconsumption in typical operating temperatures.

Unnecessary power consumption is even more important in mobile devicesas it reduces battery lifetime.

In light of the above, it would be desirable to provide a semiconductordevice in which parameters may be varied with respect to operatingtemperature.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is a block schematic diagram of a semiconductor device accordingto an embodiment.

FIG. 2 is a circuit schematic diagram of a reference voltage accordingto an embodiment.

FIG. 3 is a circuit schematic diagram of a temperature sensing circuitaccording to an embodiment.

FIG. 4 is a circuit schematic diagram of a temperature sensing circuitaccording to an embodiment.

FIG. 5 is a circuit schematic diagram of a variable resistor accordingto an embodiment.

FIG. 6 is circuit schematic diagram of a counter circuit according to anembodiment.

FIG. 7 a is a circuit schematic diagram of a counter cell according toan embodiment.

FIG. 7 b is a circuit schematic diagram of a counter cell according toan embodiment.

FIG. 7 c is a circuit schematic diagram of a counter cell according toan embodiment.

FIG. 8 is a circuit schematic diagram of a count limit detectoraccording to an embodiment.

FIG. 9 is circuit schematic diagram of a transition detector accordingto an embodiment.

FIG. 10 is a circuit schematic diagram of a control circuit according toan embodiment.

FIG. 11 is a circuit schematic diagram of a power up circuit accordingto an embodiment.

FIG. 12 is a circuit schematic diagram of a performance parameter tableaccording to an embodiment.

FIG. 13 is a circuit schematic diagram of a precharge circuit accordingto an embodiment.

FIG. 14 is a block schematic diagram of operational circuits accordingto an embodiment.

FIG. 15 is a circuit schematic diagram of a register circuit accordingto an embodiment.

FIG. 16 is a diagram of a temperature ranges set by temperature sensorcircuits according to an embodiment.

FIG. 17 is a waveform diagram illustrating the power up operation of asemiconductor device according to an embodiment.

FIG. 18 is a waveform diagram illustrating a detection of an increase intemperature from a first temperature range to a second temperature rangefor a semiconductor device according to an embodiment.

FIG. 19 is a waveform diagram illustrating a detection of a decrease intemperature from a first temperature range to a second temperature rangefor a semiconductor device according to an embodiment.

FIG. 20 is a waveform diagram the operation of a semiconductor deviceover various temperature ranges according to an embodiment.

FIG. 21 is a waveform diagram the operation of a semiconductor deviceover various temperature ranges near a maximum temperature rangeaccording to an embodiment.

FIG. 22 is a waveform diagram the operation of a semiconductor deviceover various temperature ranges near a minimum temperature rangeaccording to an embodiment.

FIG. 23 is a block schematic diagram of a semiconductor device accordingto an embodiment.

FIG. 24 is a circuit schematic diagram of a temperature sensor circuitaccording to an embodiment.

FIG. 25 is a waveform diagram illustrating the operation of asemiconductor device over various temperature ranges according to anembodiment.

FIG. 26 is a circuit schematic diagram of performance parameter adjustedcircuits according to an embodiment.

DETAILED DESCRIPTION OF THE EMBODIMENTS

According to the embodiments set forth below, a semiconductor device caninclude a temperature sensing circuit. The temperature sensing circuitscan include at least one variable resistor that can set a temperaturerange. A counter may incrementally change in accordance with atemperature of the semiconductor device changing outside of the boundsof the range. The resistance value of the at least one variable resistorcan change in response to the count output of the counter such that thetemperature range can change. Furthermore, the value of the counter mayselect parameters stored in a table to set performance parameters ofvarious operational circuits. In this way, functionality of thesemiconductor device may be assured over a large temperature rangewithout wasting power and/or degrading performance unnecessarily.

Referring now to FIG. 1, a semiconductor device according to anembodiment is set forth in a block schematic diagram and given thegeneral reference character 100.

Semiconductor device 100 may include a reference voltage generator 110,temperature sensor circuits (120 and 130), and a counter circuit 140.Semiconductor device 100 may also include a count limit detector 150, atransition detector 160, a performance parameter table 170, a controlcircuit 180, a power up circuit 190, and operational circuits 195.

Voltage generator 110 may provide a reference voltage V_(BGREF) and areference voltage V_(TEMP). Reference voltage V_(BGREF) may be areference potential that is essentially independent of temperature.Reference voltage V_(BGREF) may be provided as a reference potential totemperature sensor circuits (120 and 130). Reference voltage V_(TEMP)may be provided as a temperature dependent potential to temperaturesensor circuits (120 and 130).

Temperature sensor circuit 120 may receive reference voltages (V_(BGREF)and V_(TEMP)), count limit signal MAX, count transition signal CTD,power up signal PUP, and count value CNT[n:1] as inputs and may providean increment signal INC as an output. Temperature sensor circuit 130 mayreceive reference voltages (V_(BGREF) and V_(TEMP)), count limit signalMIN, count transition signal CTD, power up signal PUP, and count valueCNT[n:1] as inputs and may provide decrement signal DEC as an output.Temperature sensor circuit 120 may provide a temperature range upperlimit value based on the count value CNT[n:1] and temperature sensorcircuit 130 may provide a temperature range lower limit value based onthe count value CNT[n:1].

Counter circuit 140 may receive increment signal INC, decrement signalDEC, and power up signal PUP as inputs and may provide count valueCNT[n:1] as an output. Counter circuit 140 may incrementally increasecount value CNT[n:1] in response to increment signal INC transitioningfrom a logic low to a logic high level and may incrementally decreasecount value CNT[n:1] in response to decrement signal DEC transitioningfrom a logic low to a logic high level.

Count limit detector 150 may receive count value CNT[n:1] and mayprovide count limit signals (MAX and MIN) as outputs. Count limit signalMAX may transition from a logic low to a logic high level when countvalue CNT[n:1] has a maximum allowed value. Count limit signal MIN maytransition from a logic low to a logic high level when count valueCNT[n:1] has a minimum allowed value.

Transition detector 160 can receive the least significant bit CNT[1]from count value CNT[n:1] and may provide a count transition signal CTD.Count transition signal CTD may be a pulse signal generated in responseto a logic transition in the least significant bit CNT[1] from countvalue CNT[n:1].

Performance parameter table 170 may receive count value CNT[n:1] and aread signal READ as inputs and may provide performance parametersPP[m:1] as an output. Performance parameters PP[m:1] may include m bits.Performance parameter table 170 may include a non-volatile memory arrayproviding performance parameters PP[m:1] in accordance to an addresscorresponding to the value of count value CNT[n:1] in response to readsignal READ.

Control circuit 180 may receive a power up signal PUPD and counttransition signal CTD and may provide read signal READ and a load signalLOAD as outputs. Power up circuit 190 may provide power up signals (PUPand PUPD) as outputs in response to power being applied to semiconductordevice 100.

Operational circuits 195 may perceive performance parameters PP[m:1] andload signal LOAD. Operational circuits 195 may latch performanceparameters PP[m:1] into latches in response to load signal LOAD. Thelatched performance parameters may modify the operation of circuitry,for example, increase or decrease time delays, change the magnitude ofpotential levels, and/or vary threshold voltages in IGFETs, as just afew examples. In this way, circuitry in operational circuits 195 mayoperate over a large temperature range without unduly wasting power oradversely affecting speed at one temperature in order to providefunctionality margin at another temperature.

Referring now to FIG. 2, reference voltage generator 110 is set forth ina circuit schematic diagram.

Reference voltage generator 110 may include a bandgap reference inputsection 210 and a bandgap reference output section 220. Bandgapreference input section 210 may provide a voltage V_(TEMP). Thepotential of voltage V_(TEMP) may change inversely to the change in thetemperature of the semiconductor device 100. Bandgap reference outputsection 220 can receive voltage V_(TEMP) and may provide an essentiallytemperature independent reference voltage V_(BGREF). An example of abandgap reference output section providing a temperature independentreference voltage can be seen in U.S. Pat. No. 6,150,872 incorporatedherein by reference or U.S. Pat. No. 6,549,065 incorporated herein byreference, as just two examples.

Bandgap reference input section 210 may include bipolar transistors(Q202 and Q204), resistor R200, transistors (P202 and P204), andamplifier AMP200. Bipolar transistor Q202 may have an emitter commonlyconnected to a negative input of amplifier AMP200 and a drain oftransistor P202. Bipolar transistor Q204 may have an emitter connectedto a first terminal of resistor R200. Bipolar transistors (Q202 andQ204) may have bases and collectors commonly connected to a groundterminal. Alternatively, in some cases the bases and collectors may beconnected to a negatively charged substrate voltage, as just one moreexample. Resistor R200 may have a second terminal commonly connected toa positive input of amplifier AMP200 and a drain of transistor P204.Amplifier AMP200 may provide voltage V_(TEMP) as an output, which isalso fed back to the gates of transistors (P202 and P204). Transistors(P202 and P204) may have sources connected to a power supply voltageVcc.

Bipolar transistors (Q202 and Q204) may be substrate pnp bipolartransistors and transistor Q204 may be sized at nQ202. Transistors (P202and P204) may be p-channel insulated gate field effect transistors(IGFET), such as MOSFETs.

Referring now to FIG. 3, temperature sensor circuit 120 according to anembodiment is set forth in a circuit schematic diagram. Temperaturesensor circuit 120 may receive reference voltages (V_(BGREF) andV_(TEMP)), count limit signal MAX, count transition signal CTD, power upsignal PUP, and count value CNT[n:1] as inputs and may provide anincrement signal INC as an output.

Temperature sensor circuit 120 can include a temperature sensing portion302 and an increment signal output portion 304 Temperature sensingportion 302 can receive reference voltages (V_(BGREF) and V_(TEMP)), andcount value CNT[n:1] as inputs and may provide a temperature detectsignal TD1 as an output. Temperature increment signal output portion 304can receive temperature detect signal TD1, count limit signal MAX, counttransition signal CTD, and power up signal PUP as inputs and may providean increment signal INC as an output.

Temperature sensing portion 302 can include a p-channel insulated gatefield effect transistor (IGFET) P300, a variable resistor 310, aresistor R300, and an amplifier AMP300. Increment signal output portion304 can include a NOR logic gate G300, an inverter logic gate G310, apass gate PG300, and an n-channel IGFET N300.

P-channel IGFET P300 may have a source terminal connected to a powersupply potential VDD, a drain commonly connected to a first terminal ofvariable resistor 310 and a positive input terminal of amplifier AMP300at node ND300, and a gate terminal connected to receive voltageV_(TEMP). The potential of voltage V_(TEMP) may change inversely to thechange in the temperature of the semiconductor device 100. Variableresistor 310 may receive count value CNT[n:1] as inputs and may have asecond terminal connected to a first terminal of resistor R300. ResistorR300 may have a second terminal connected to a ground potential.Amplifier AMP300 may have a negative input terminal connected to receivevoltage V_(BGREF). Voltage V_(BGREF) may not vary with temperature andmay have an essentially constant potential. Amplifier circuit AMP300 mayprovide temperature detect signal TD1 as an output.

NOR logic gate G300 may receive count limit signal MAX, power up signalPUP, and count transition signal CTD as inputs and may provide anoutput. Inverter logic gate G310 may receive the output of NOR logicgate G300 at an input terminal and may provide an output. Pass gatePG300 may receive the output of NOR logic gate G300 and inverter logicgate G310 as inputs and may provide a controllable impedance pathbetween the output of amplifier AMP300 and the increment signal INC.N-channel IGFET N300 may have a drain terminal connected to incrementsignal INC, a source connected to a ground potential and a gate terminalconnected to receive the output of inverter logic gate G310.

Pass gate PG300 may include an n-channel IGFET N310 and a p-channelIGFET P310 having source/drain terminals connected in parallel betweenthe output of amplifier AMP300 and an output terminal to provideincrement signal INC. N-channel IGFET N310 may receive the output of NORlogic gate G300 at a gate terminal. P-channel IGFET P310 may receive theoutput of inverter logic gate G310 at a gate terminal. In this way, passgate PG300 may provide a controllable impedance path between the outputof amplifier AMP300 and increment signal INC in response to the outputof NOR logic gate G300.

Referring now to FIG. 4, temperature sensor circuit 130 is set forth ina circuit schematic diagram. Temperature sensor circuit 130 may receivereference voltages (V_(BGREF) and V_(TEMP)), count limit signal MIN,count transition signal CTD, power up signal PUP, and count valueCNT[n:1] as inputs and may provide decrement signal DEC as an output.

Temperature sensor circuit 130 can include a temperature sensing portion402 and a decrement signal output portion 404 Temperature sensingportion 402 can receive reference voltages (V_(BGREF) and V_(TEMP)), andcount value CNT[n:1] as inputs and may provide an temperature detectsignal TD2 as an output. Decrement signal output portion 404 can receivetemperature detect signal TD2, count limit signal MIN, count transitionsignal CTD, and power up signal PUP as inputs and may provide decrementsignal DEC as an output.

Temperature sensing portion 402 can include a p-channel insulated gatefield effect transistor (IGFET) P400, a variable resistor 410, aresistor R400, and an amplifier AMP400. Decrement signal output portion404 can include a NOR logic gate G400, an inverter logic gate G410, apass gate PG400, inverter logic gate G420, and an n-channel IGFET N400.

P-channel IGFET P400 may have a source terminal connected to a powersupply potential VDD, a drain commonly connected to a first terminal ofvariable resistor 410 and a positive input terminal of amplifier AMP400at node ND400, and a gate terminal connected to receive voltageV_(TEMP). The potential of reference voltage V_(TEMP) may changeinversely to the change in the temperature of the semiconductor device100. Variable resistor 410 may receive count value CNT[n:1] as inputsand may have a second terminal connected to a first terminal of resistorR400. Resistor R400 may have a second terminal connected to a groundpotential. Amplifier AMP400 may have a negative input terminal connectedto receive reference voltage V_(BGREF). Reference voltage V_(BGREF) maynot vary with temperature and may have an essentially constantpotential. Amplifier AMP400 may provide temperature detect signal TD2 asan output.

NOR logic gate G400 may receive count limit signal MIN, power up signalPUP, and count transition signal CTD as inputs and may provide anoutput. Inverter logic gate G410 may receive the output of NOR logicgate G400 at an input terminal and may provide an output. Inverter logicgate G420 may receive the output of amplifier AMP400 at an inputterminal and may provide an output. Pass gate PG400 may receive theoutput of NOR logic gate G400 and inverter logic gate G410 as inputs andmay provide a controllable impedance path between the output of inverterlogic gate G420 and the decrement signal DEC. N-channel IGFET N400 mayhave a drain terminal connected to decrement signal DEC, a sourceconnected to a ground potential and a gate terminal connected to receivethe output of inverter logic gate G410.

Pass gate PG400 may include an n-channel IGFET N410 and a p-channelIGFET P410 having source/drain terminals connected in parallel betweenthe output of inverter logic gate G420 and decrement signal DEC.N-channel IGFET N410 may receive the output of NOR logic gate G400 at agate terminal. P-channel IGFET P410 may receive the output of inverterlogic gate G410 at a gate terminal. In this way, pass gate PG400 mayprovide a controllable impedance path between the output of inverterlogic gate G420 and decrement signal DEC in response to the output ofNOR logic gate G400.

Temperature sensor circuit 120 may provide a temperature range upperlimit value based on the count value CNT[n:1] and temperature sensorcircuit 130 may provide a temperature range lower limit value based onthe count value CNT[n:1]. Increment signal INC may transition from a lowlogic level to a high logic level in response to the temperature ofsemiconductor device 100 transitioning from within the temperature rangeto the temperature range upper limit value. Decrement signal DEC maytransition from a low logic level to a high logic level in response tothe temperature of semiconductor device 100 transitioning from withinthe temperature range to the temperature range lower limit value.

Referring now to FIG. 5, a variable resistor according to an embodimentis set forth in a block schematic diagram and given the generalreference character 500. Variable resistor 500 may be used as variableresistor 310 or variable resistor 410 in temperature sensor circuits(120 and 130), respectively.

Variable resistor 500 may include resistors (R510-1 to R510-n) connectedin series. Resistor R510-1 may have a first terminal connected tovoltage dividing node ND510 (corresponding to a node ND300 fortemperature sensing circuit 120 and a node ND400 for temperature sensingcircuit 130). Resistor R510-1 may have a second terminal connected to afirst terminal of resistor R510-2. Resistor R510-2 may have a secondterminal connected to resistor R510-3. This series connection may berepeated until the last resistor R510-n may have a second terminalconnected to node N520 (corresponding to the second terminal of resistorR300 in temperature sensor circuit 120 and the second terminal ofresistor R400 in temperature sensor circuit 130).

Variable resistor 500 may include transistors (N510-1 to N510-n). Eachtransistor (N510-1 to N510-n) has a drain connected to a first terminalof a resistor (R510-1 to R510-n), respectively, and a source connectedto a second terminal of a resistor (R510-1 to R510-n), respectively.Each transistor (N510-1 to N510-n) receives a respective count value bitCNT[0] to CNT[n] at a respective gate terminal.

Transistors (N510-1 to N510-n) may be n-channel IGFETs, for example.

Transistors (N510-1 to N510-n) can each form a shunt for a respectiveresistor (R510-1 to R510-n) when a respective count value bit CNT[1] toCNT[n] is at a high level (i.e., the respective transistor (N510-1 toN510-n) is turned on). When a respective count value bit (CNT[1] toCNT[n]) is at a low level, the respective transistor (N510-1 to N510-n)is turned off and the respective resistor (R510-1 to R510-n) is includedin the resistance value of variable resistor 500. In this way, aresistance value for variable resistor 500 may be selected. Theresistance value for variable resistor 500 may include the cumulativevalues of resistors (R510-1 to R510-n) not shunted by respectivetransistors (N510-1 to N510-n).

Resistors (R510-1 to R510-n) may respectively provide a binary codeddecimal resistance value in response to count value (CNT[1] to CNT[n]),such that resistor R510-1 may have a resistance value of R, resistorR510-1 may have a resistance value of 2R, resistor R510-2 may have aresistance value of 4R, resistor R510-3 may have a resistance value of8R, and so on, and resistor R510-n may have a resistance value of(2^(n))R.

Referring now to FIG. 6, a counter circuit 140 according to anembodiment is set forth in a circuit schematic diagram. Counter circuit140 may receive increment signal INC, decrement signal DEC and power upsignal PUP as inputs at input terminals and may provide count value bits(CNT[1] to CNT[n]) as outputs at output terminals. Counter circuit 140may include a logic gate G510, a delay stage INVD, and counter cells(CS1 to CSn).

Logic gate G510 may receive increment and decrement signals (INC andDEC) as inputs and may provide an output. Logic gate G510 may be a NORlogic gate. Delay stage INVD may receive the output from logic gate G510at an input terminal and may provide count clock signal CCLK at anoutput terminal. The propagation time delay of delay stage INVD may besufficient to allow increment or decrement signal (INC and DEC) topropagate through counter stages (CS1 to CSn−1 to provide toggle signalTGn−1 as an input to counter stage CSn before counter clock signal CCLKis provided to incrementally change the value of count value CNT[n:1].

Counter cell CS1 may receive increment signal INC at a count up inputterminal CUIN, decrement signal DEC at a count down input terminal CDIN,power supply potential VDD at a toggle input terminal TGIN, and countclock signal CCLK at a clock input terminal CLK. Counter cell CS1 mayreceive a ground potential at a preset input terminal PRE and power upsignal PUP at a clear input terminal CLR. Counter cell CS1 may provide acount up signal CUP1 at a count up output terminal CUP, a toggle signalTG1 at a toggle output terminal TGO, a count down signal CDN1 at a countdown output terminal CDN, and a count value bit CNT[1] at a count bitoutput terminal CNT.

Counter cell CS2 may receive count up signal CUP1 at a count up inputterminal CUIN, count down signal CDN1 at a count down input terminalCDIN, toggle signal TG1 at a toggle input terminal TGIN, and count clocksignal CCLK at a clock input terminal CLK. Counter cell CS2 may receivea ground potential at a preset input terminal PRE and power up signalPUP at a clear input terminal CLR. Counter cell CS2 may provide a countup signal CUP2 at a count up output terminal CUP, a toggle signal TG2 ata toggle output terminal TGO, a count down signal CDN2 at a count downoutput terminal CDN, and a count value bit CNT[2] at a count bit outputterminal CNT.

Counter cell CS3 may receive count up signal CUP2 at a count up inputterminal CUIN, count down signal CDN2 at a count down input terminalCDIN, toggle signal TG2 at a toggle input terminal TGIN, and count clocksignal CCLK at a clock input terminal CLK. Counter cell CS3 may receivea ground potential at a preset input terminal PRE and power up signalPUP at a clear input terminal CLR. Counter cell CS3 may provide a countup signal CUP3 at a count up output terminal CUP, a toggle signal TG3 ata toggle output terminal TGO, a count down signal CDN3 at a count downoutput terminal CDN, and a count value bit CNT[3] at a count bit outputterminal CNT.

Counter cell CS4 may receive count up signal CUP3 at a count up inputterminal CUIN, count down signal CDN3 at a count down input terminalCDIN, toggle signal TG3 at a toggle input terminal TGIN, and count clocksignal CCLK at a clock input terminal CLK. Counter cell CS4 may receivea ground potential at a preset input terminal PRE and power up signalPUP at a clear input terminal CLR. Counter cell CS4 may provide a countup signal CUP4 at a count up output terminal CUP, a toggle signal TG4 ata toggle output terminal TGO, a count down signal CDN4 at a count downoutput terminal CDN, and a count value bit CNT[4] at a count bit outputterminal CNT.

Counter cell CSn−1 may receive count up signal CUPn−2 at a count upinput terminal CUIN, count down signal CDNn−2 at a count down inputterminal CDIN, toggle signal TGn−2 at a toggle input terminal TGIN, andcount clock signal CCLK at a clock input terminal CLK. Counter cellCSn−1 may receive a ground potential at a preset input terminal PRE andpower up signal PUP at a clear input terminal CLR. Counter cell CSn−1may provide a toggle signal TGn−1 at a toggle output terminal TGO, and acount value bit CNT[n−1] at a count bit output terminal CNT.

Counter cell CSn may receive toggle signal TGn−1 at a toggle inputterminal TGIN, and count clock signal CCLK at a clock input terminalCLK. Counter cell CSn may receive a ground potential at a clear inputterminal CLR and power up signal PUP at a preset input terminal CLR.Counter cell CSn may provide a count value bit CNT[n] at a count valueoutput terminal CNT.

It is understood that there may be any number of counter cells CSdisposed in series between counter cell CS4 and CSn−1 to provide apredetermined number “n” of count bits.

Referring now to FIGS. 7 a to 7 c, counter cells according to anembodiment are set forth in circuit schematic diagrams and given thegeneral reference characters 700 a to 700 c, respectively.

Counter cell 700 a may include count up input terminal CUIN, presetinput terminal PRE, toggle input terminal TGIN, clear input terminalCLR, count down input terminal CDIN, and clock input terminal CLK.Counter cell 700 a may further include count bit output terminal CNT,count up output terminal CUP, toggle output terminal TGO, and count downoutput terminal CDN.

Counter cell 700 a may be used as counter cells (CS1 to CS4) in countercircuit 140 of FIG. 6.

Counter cell 700 a may include a flip-flop circuit 710 a, and logicgates (G710 a, G720 a, G730 a, G740 a, and G750 a).

Flip-flop circuit 710 a may have commonly connected input terminals (Jand K) connected to receive an input signal at toggle input terminalTGIN. Flip-flop circuit 710 a may receive clock input terminal CLK at aflip-flop clock input terminal CLKF, preset input terminal PRE at aflip-flop preset input terminal PREF, and clear input terminal CLR at aflip-flop clear input terminal CLRF. Flip-flop circuit 710 a may includeoutput terminals (Q and /Q). Output terminal Q may be connected to countbit output terminal CNT to provide a count value bit. Flip-flop circuit710 a may be a J-K flip flop circuit.

Logic gate G710 a may have a first input terminal connected to receive asignal from count up input terminal CUIN as an input signal and a secondinput terminal connected to receive a count value bit from count bitoutput terminal CNT. Logic gate G710 a may provide an output signal atan output terminal. Logic gate G710 a may be a NAND logic gate.

Logic gate G720 a may have a first input terminal connected to receivean input signal from count down input terminal CDIN and a second inputterminal connected to receive a complementary count value bit fromoutput terminal /Q of flip-flop circuit 710 a. Logic gate G720 a mayprovide an output signal at an output terminal. Logic gate G720 a may bea NAND logic gate.

Logic gate G730 a may receive an output from logic gate G710 a at aninput terminal and may provide an output signal to count up outputterminal CUP. Logic gate G730 a may be an inverter logic gate.

Logic gate G740 a may have a first input terminal connected to receivean output signal from logic gate 710 a and a second input terminalconnected to receive an output signal from logic gate 720 a. Logic gateG740 a may provide an output signal to toggle output terminal TGO. Logicgate G740 a may be a NAND logic gate.

Logic gate G750 a may receive an output from logic gate G720 a at aninput terminal and may provide an output signal to count down outputterminal CDN. Logic gate G750 a may be an inverter logic gate.

Counter cell 700 b may be used as counter cell CSn−1 in counter circuit140 of FIG. 6.

Counter cell 700 b may include a flip-flop circuit 710 b, and logicgates (G710 b, G720 b, can G730 b).

Flip-flop circuit 710 b may have commonly connected input terminals (Jand K) connected to receive an input signal at toggle input terminalTGIN. Flip-flop circuit 710 b may receive clock input terminal CLK at aflip-flop clock input terminal CLKF, preset input terminal PRE at aflip-flop preset input terminal PREF, and clear input terminal CLR at aflip-flop clear input terminal CLRF. Flip-flop circuit 710 b may includeoutput terminals (Q and /Q). Output terminal Q may be connected to countbit output terminal CNT to provide a count value bit. Flip-flop circuit710 b may be a J-K flip flop circuit.

Logic gate G710 b may have a first input terminal connected to receive asignal from count up input terminal CUIN as an input signal and a secondinput terminal connected to receive a count value bit from count bitoutput terminal CNT. Logic gate G710 b may provide an output signal atan output terminal. Logic gate G710 b may be a NAND logic gate.

Logic gate G720 b may have a first input terminal connected to receivean input signal from count down input terminal CDIN and a second inputterminal connected to receive a complementary count value bit fromoutput terminal /Q of flip-flop circuit 710 b. Logic gate G720 b mayprovide an output signal at an output terminal. Logic gate G720 b may bea NAND logic gate.

Logic gate G730 b may have a first input terminal connected to receivethe output signal from logic gate 710 b and a second input terminalconnected to receive the output signal from logic gate 720 b. Logic gateG730 b may provide an output signal to toggle output terminal TGO. Logicgate G730 b may be a NAND logic gate.

Counter cell 700 c may be used as counter cell CSn in counter circuit140 of FIG. 6.

Counter cell 700 c may include a flip-flop circuit 710 c.

Flip-flop circuit 710 c may have commonly connected input terminals (Jand K) connected to receive an input signal at toggle input terminalTGIN. Flip-flop circuit 710 c may receive clock input terminal CLK at aflip-flop clock input terminal CLKF, preset input terminal PRE at aflip-flop preset input terminal PREF, and clear input terminal CLR at aflip-flop clear input terminal CLRF. Flip-flop circuit 710 c may includeoutput terminals (Q and /Q). Output terminal Q may be connected to countbit output terminal CNT to provide a count value bit. Flip-flop circuit710 c may be a J-K flip flop circuit.

Referring now to FIG. 8, count limit detector 150 is set forth in acircuit schematic diagram.

Count limit detector 150 may include a maximum count limit circuit 800 aand a minimum count limit circuit 800 b.

Maximum count limit circuit 800 a can receive count value CNT[n:1] asinputs and provide count limit signal MAX as an output. Maximum countlimit circuit 800 a can include logic gate circuits (G810, G820, andG830).

Logic gate circuit G810 can receive count value bits (CNT[1], CNT[2],and CNT[3]) at input terminals and may provide an output signal at anoutput terminal. Logic gate circuit G810 may be a NAND logic gatecircuit.

Logic gate circuit G820 can receive count value bits (CNT[n−1] andCNT[n]) at input terminals and may provide an output signal at an outputterminal. Logic gate circuit G820 may be a NAND logic gate circuit.

Logic gate circuit G830 can receive the output signal of logic gatecircuit G810 at a first input terminal and output signal of logic gatecircuit G820 at a second input terminal and may provide count limitsignal MAX at an output terminal. Logic gate circuit G830 may be a NORlogic gate circuit.

Minimum count limit circuit 800 b can receive count value CNT[n:1] asinputs and provide count limit signal MIN as an output. Maximum countlimit circuit 800 b can include logic gate circuits (G840, G850, G860,and G870).

Logic gate circuit G840 can receive count value bits (CNT[1], CNT[2],and CNT[3]) at input terminals and may provide an output signal at anoutput terminal. Logic gate circuit G840 may be a NOR logic gatecircuit.

Logic gate circuit G850 can receive count value bits (CNT[n−1] andCNT[n]) at input terminals and may provide an output signal at an outputterminal. Logic gate circuit G850 may be a NOR logic gate circuit.

Logic gate circuit G860 can receive the output signal of logic gatecircuit G840 at a first input terminal and output signal of logic gatecircuit G850 at a second input terminal and may provide an output signalat an output terminal. Logic gate circuit G860 may be a NAND logic gatecircuit.

Logic gate circuit G870 can receive the output signal of logic gatecircuit G860 at an input terminal and may provide count limit signal MINat an output terminal. Logic gate circuit G870 may be an inverter logicgate circuit.

It is understood that there may be a predetermined similar logic gatesinterposed between logic gates (G810 and G820) to accommodate any numberof bits in count value CNT[n:1] such that maximum count limit circuit800 a performs a logic AND of count value CNT[n:1]. Likewise, it isunderstood that there may be a predetermined similar logic gatesinterposed between logic gates (G840 and G850) to accommodate any numberof bits in count value CNT[n:1] such that minimum count limit circuit800 b performs a logic NOR of count value CNT[n:1].

Referring now to FIG. 9, transition detector 160 is set forth in acircuit schematic diagram.

Transition detector 160 may receive the least significant bit CNT[1]from count value CNT[n:1] as an input and may provide a count transitionsignal CTD as an output.

Transition detector 160 may include logic gate circuits (G910, G920, andG930) and a delay circuit D910.

Logic gate circuit G910 can receive the least significant bit CNT[1]from count value CNT[n:1] at an input terminal and may provide an outputto an output terminal. Logic gate circuit G910 may be an invertercircuit.

Delay circuit D910 may receive the output of logic gate circuit G910 atan input terminal and may provide an output at an output terminal. Delaycircuit D910 may delay both the rising edge and the falling edge of theoutput from logic gate circuit G910 to provide a delayed signal at theoutput terminal of delay circuit D910.

Logic gate circuit G920 may receive the least significant bit CNT[1]from count value CNT[n:1] at a first input terminal and the delayedsignal provided at the output terminal of delay circuit D910 at a secondinput terminal and may provide an output at an output terminal. Logicgate circuit G920 may be an exclusive NOR (XNOR) circuit.

Logic gate circuit G930 can receive the output of logic gate circuitG920 at an input terminal and may provide count transition signal CTD anoutput terminal. Logic gate circuit G930 may be an inverter circuit.

The operation of transition detector 160 will now be discussed. Whenleast significant bit CNT[1] from count value CNT[n:1] is at a low logiclevel, the first input of logic gate circuit G920 is at a logic lowlevel and the second input terminal of logic gate circuit G920 is at alogic high level. In this case, the output of logic gate circuit G920(XNOR gate) is a logic high. With the output of logic gate circuit G920at a logic high, the output of logic gate circuit G930 (inverter) is alogic low. In this way, count transition signal CTD may be a logic lowlevel. When the least significant bit CNT[1] from count value CNT[n:1]transitions from a logic low level to a logic high level, the firstinput terminal of logic gate circuit G920 is at a logic high level. Atthis time, the logic transition has not propagated through delay circuitD910 and the second input terminal of logic gate circuit G920 remains ata logic high level. With both input terminals of logic gate circuit G920(XNOR gate) at a logic high level, the output of logic gate circuit G920may transition to a logic low level and the output of logic gate circuitG930 (an inverter) may be a logic high level. After the logic transitionpropagates through, delay circuit D910, the second input terminal oflogic gate G920 may transition to a logic low level. With the firstinput terminal of logic gate circuit G920 at a logic high level and thesecond input terminal at a logic low level, the output of logic gatecircuit G920 may transition to a logic high level and the output oflogic gate G930 may transition to a logic low level. In this way, counttransition signal CTD may be a pulse generated in response to atransition in the When least significant bit CNT[1] from count valueCNT[n:1]. The pulse width of count transition signal CTD may beessentially determined by the propagation delay of delay circuit D910.In a similar manner, transition detector 160 can generate a counttransition signal CTD having a pulse in response to a high to low logictransition of least significant bit CNT[1] from count value CNT[n:1].

Referring now to FIG. 10, a control circuit 180 is set forth in acircuit schematic diagram. Control circuit 180 can be used as controlcircuit 180 in semiconductor device 100 of FIG. 1.

Control circuit 180 may receive power up signal PUPD and counttransition signal CTD at input terminals and may provide read signalREAD and load signal LOAD as outputs at respective output terminals.

Control circuit 180 may include a read generating circuit 1010 and aload generating circuit 1030. Read generating circuit 1010 may receivepower up signal PUPD and count transition signal CTD at input terminalsand may provide read signal READ at an output terminal. Load generatingcircuit 130 may receive read signal READ at an input terminal and mayprovide load signal LOAD at an output terminal.

Read generating circuit 1010 may include pulse generating circuit 1012and logic gates (G1016, G1018, and G1020). Pulse generating circuit 1012may receive power up signal PUPD as an input and may provide a pulseoutput at an output terminal. Logic gate G1016 may receive the pulseoutput of pulse generating circuit 1012 at an input terminal and mayprovide an output to an output terminal. Logic gate G1016 may be aninverter circuit. Logic gate G1018 may receive count transition signalCTD at an input terminal and may provide an output to an outputterminal. Logic gate G1018 may be an inverter circuit. Logic gate G1020may receive the output of logic gate G1016 at a first input terminal andthe output of logic gate G1018 at a second input terminal and mayprovide read signal READ at an output terminal. Logic gate G1020 may bea NAND logic gate.

Load generating circuit 1030 can include delay circuit D1032 and pulsegenerating circuit 1032. Delay circuit D1032 may receive read signalREAD at an input terminal and may provide an output at an outputterminal. Pulse generating circuit 1032 may receive the output of delaycircuit D1032 at an input terminal and may provide load signal LOAD atan output terminal.

Pulse generating circuit 1032 can include logic gates (G1032, G1034, andG1036) and delay circuit D1034. Logic gate G1032 may receive the outputof delay circuit at an input terminal and may provide an output at anoutput terminal. Logic gate G1032 may be an inverter logic gate. Delaycircuit D1032 may receive the output of logic gate G1032 at an inputterminal and may provide an output at an output terminal. Logic gateG1034 can receive the output of delay circuit D1034 at a first inputterminal and the output of delay circuit D1032 at a second inputterminal and may provide an output at an output terminal. Logic gateG1034 may be a NAND logic gate. Logic gate G1036 may receive the outputof logic gate G1034 at an input terminal and may provide load signalLOAD at an output terminal.

The operation of control circuit 180 will now be explained. Pulsegenerating circuit 1032 may create a logic high pulse in response topower up signal PUPD transitioning from a logic high to a logic lowlevel. When the pulse output of pulse generating circuit 1012 is high,the output of logic gate G1010 will be at a logic low. With the outputof logic gate G1016 at a logic low level, read signal READ may be at alogic high. Read signal READ may be a logic high pulse having a pulsewidth essentially determined by the propagation delay of delay circuitD1032 generated in response to power up signal PUPD transitioning from alogic high to a logic low level. Otherwise, read signal READ may begenerated as a pulse signal (logic high pulse) in response to the counttransition signal CTD (via logic gate (G1018 and G1020)). In this case,the pulse width of read signal READ may essentially be set by thepropagation delay of delay circuit D910 in count transition detectorD910.

Read signal READ may propagate through delay circuit D1032. When a lowto high transition read signal READ propagates through delay circuitD1032, pulse generator 1032 in load signal generating circuit 1030 mayprovide a high going pulse for load signal LOAD. In this way, loadsignal LOAD may be a high going pulse generated a predetermined delayafter the read signal transitions from low to high. The predetermineddelay can be essentially the propagation delay of delay circuit D1032and the pulse width of load signal LOAD may be essentially thepropagation delay of delay circuit D1034 in pulse generating circuit1032.

Referring now to FIG. 11, a power up circuit 190 is set forth in acircuit schematic diagram.

Power up circuit 190 may generate power up signals (PUP and PUPD) inresponse to a detection of a power supply Vext being energized to apredetermined potential.

Power up circuit 190 may include a charging circuit 1110, a first powerup signal generating circuit 1120 and a second power up signalgenerating circuit 1130. Charging circuit 1110 can receive power supplyVext a feedback node N2 as inputs and may provide an output at a chargenode N1. First power up signal generating circuit 1120 may have an inputterminal connected to charge node N1 and may provide an output atfeedback node N2 and power up signal PUP at an output terminal. Secondpower up signal generating circuit 1130 may receive feedback node N2 atan input terminal and may provide power up signal PUPD at an outputterminal.

Charging circuit 1110 can include p-channel IGFETs (P1112 and P1114),n-channel IGFETs (N1112 and N1114), and a capacitor C1112. P-channelIGFET P1112 may receive a power supply Vext at a source terminal and mayhave gate and drain terminals commonly connected to a charge node N1.P-channel IGFET P1114 may receive power supply Vext at a sourceterminal, feedback node N2 at a gate terminal, and may have a drainterminal connected to charge node N1. N-channel IGFET N1112 may receivea ground reference potential at a source terminal, feedback node N2 at agate terminal, and may have a drain terminal commonly connected to thesource terminal of n-channel IGFET N1114. N-channel IGFET N1114 may havedrain and gate terminals commonly connected to charge node N1.

First power up signal generating circuit 1120 can include logic gates(G1122, G1124, G1126, G1128, and G1129) and capacitors (C1122, C1124,and C1126). Logic gate G1122 may have an input terminal connected tocharge node N1 and an output terminal commonly connected to a firstterminal of capacitor C1122 and an input terminal of logic gate G1124.Capacitor C1122 may have a second terminal connected to power supplyVext. Logic gate G1124 may have an output terminal commonly connected toa first terminal of capacitor C1124 and an input terminal of logic gateG1126. Capacitor C1124 may have a second terminal connected to a groundreference potential. Logic gate G1126 may have a second terminalconnected to feedback node N2. Capacitor C1126 may have a first terminalconnected to feedback node N2 and a second terminal connected to powersupply Vext. Logic gate G1128 can have an input terminal connected tofeedback node N2 and an output terminal connected to an input terminalof logic gate G1129. Logic gate G1129 may provide power up signal PUP atan output terminal. Logic gates (G1122, G1124, G1126, G1128, and G1129)may be inverter circuits.

Second power up signal generating circuit 1130 may include (G1132,G1134, G1136, and G1138) and capacitors (C1132 and C1134). Logic gateG1132 may have an input terminal connected to feedback node N2 and anoutput terminal commonly connected to a first terminal of capacitorC1132 and an input terminal of logic gate G1134. Capacitor C1122 mayhave a second terminal connected to a ground reference potential. Logicgate G1134 can an output terminal commonly connected to a first terminalof capacitor C1134 and an input terminal of logic gate G1136. CapacitorC1134 may have a second terminal connected to power supply Vext. Logicgate G1136 can have an output terminal connected to an input terminal oflogic gate G1138. Logic gate G1138 may provide power up signal PUPD atan output terminal. Logic gates (G1132, G1134, G1136, and G1138) may beinverter circuits.

The operation of power up circuit 190 will now be explained. Whensemiconductor device 100 becomes powered up, a power supply Vext maytransition from a discharged potential (i.e. ground) to a chargedpotential (i.e. the operating potential). Power up circuit 190 generatespower up signals (PUP and PUPD) in response to this potentialtransition. When power supply Vext rises, capacitors (C1122, C1126, andC1134) may pull connected nodes toward the potential of power supplyVext, while capacitors (C1112, C1124, and C1132) may essentially, keeptheir connected nodes at the ground potential. With feedback node N2 atessentially, a potential of power supply Vext, power up signal PUP maybe at a high logic level and with the node connected to capacitor C1134at essentially, a potential of power supply Vext, power up signal PUPDmay be at a high logic level. Furthermore, n-channel IGFET N1112 incharging circuit 1110 may be turned on and p-channel IGFET P1114 may beturned off. In this way, a current path may be enabled through seriesconnected p-channel IGFET P1112, n-channel IGFET N1114, and n-channelIGFET N1112 to provide charge to charge node N1. Charge node N1 chargesslowly, however once charge node N1 reaches to a threshold voltage (i.e.trip point) of logic gate G1122 (inverter) in first power up signalgenerating circuit 1120, capacitor C1122 may begin discharging toward aground potential. Once the potential of capacitor C1122 reaches to athreshold voltage of logic gate G1124 (inverter) in first power upsignal generating circuit 1120, capacitor C1124 may begin chargingtoward the potential of power supply Vext. This may continue untilcapacitor C1126 reaches a threshold voltage of logic gate G1128, inwhich power up signal PUP may transition from a logic high to a logiclow level. Also, at this time, p-channel IGFET P1114 in charging circuit1110 may turn on and re-channel IGFET N1114 may turn off to eliminatethe current path from supply potential Vext and the ground potential.

A propagation delay later (determined by charging capacitor C1132 anddischarging capacitor C1134 in second power up signal generating circuit1130), power up signal PUPD may transition from a logic high to a logiclow level.

In this way, power up circuit 190 may generate power up signals PUP andPUPD in response to semiconductor device 100 initially receive anoperating power supply potential.

Referring now to FIG. 12, performance parameter table 170 is set forthin a circuit schematic diagram.

Performance parameter table 170 may receive count value (CNT[1] toCNT[n]) and a read signal READ as inputs and may provide performanceparameters (PP1 to PPm) as an output. Performance parameters (PP1 toPPm) may include m bits. Performance parameter table 170 may be anon-volatile memory array providing performance parameters (PP1 to PPm)in accordance to an address corresponding to the value of count value(CNT[1] to CNT[n]) in response to read signal READ.

Performance parameter table 170 may include a row selection circuit1210, a precharge circuit 1220 and an array of memory cells MC.

Row selection circuit 1210 may be enabled by read signal READ toactivate a predetermined word line (WL1 to WLx, where x=2^(n)) inresponse to the value of count value (CNT[1] to CNT[n]). Prechargecircuit 1220 may be activated to drive each column line (providingperformance parameters (PP1 to PPm) to a first logic level in responseto read signal READ being in an inactive state and may be disabled toallow a selected row of memory cells MC to drive respective column lineswhen the predetermined word line (WL1 to WLx, where x=2^(n)) isactivated. In this way, programmed values in a row of memory cells MCmay be used to provide a predetermined value to performance parameters(PP1 to PPm).

Referring now to FIG. 13, a circuit schematic diagram of prechargecircuit 1220 is set forth in a circuit schematic diagram.

Precharge circuit 1220 can include a p-channel IGFET P1300 for eachcolumn line (providing performance parameters (PP1 to PPm) inperformance parameter table 170. P-channel IGFET P1300 may have a sourceterminal connected to a power supply potential VDD, a drain terminalconnected to a respective column line (PPy, where y=1−m) and a gateterminal connected to receive read signal READ. Precharge circuit 1220may provide a controllable impedance path between power supply potentialVDD and a respective column line (PPy, where y=1−m) in response to readsignal READ. Precharge circuit 1220 may provide a low impedance pathbetween power supply potential VDD and a respective column line (PPy,where y=1−m) when read signal READ is in a first logic level (logiclow), and a high impedance path between power supply potential VDD and arespective column line (PPy, where y=1−m) when read signal READ is in asecond logic level (logic high).

Referring now to FIG. 14, operational circuits 195 are set forth in ablock schematic diagram. Operational circuits can include registers 1410and performance parameter adjusted (adjustable) circuits 1420.Performance parameter adjusted circuits 1420 may have operationalaspects adjusted in accordance with latched performance parametersPPL[m:1] latched into registers 1420.

Registers 1410 may receive performance parameters PP[m:1] and loadsignal LOAD as inputs and may provide latched performance parametersPPL[m:1] as outputs. Performance parameter adjusted circuits 1420 mayreceive latched performance parameters PPL[m:1]. Performance parameteradjusted circuits 1420 may include a plurality of circuits. For example,performance parameter adjusted circuits 1420 can include an outputbuffer voltage generating circuit 1422, a DRAM refresh circuit 1424, aword line low potential generating circuit 1426, P-channel IGFET bodybias potential generating circuit 1428, N-channel IGFET body biaspotential generating circuit 1430, output buffer circuit 1432, an arraypotential generating circuit 1434, a peripheral potential generatingcircuit 1436 and a VPP generating circuit 1438.

It is understood that a unique plurality (subset) of latched performanceparameters PPL[m:1] may be respectively provided to each performanceparameter adjusted circuits 1420 including output buffer voltagegenerating circuit 1422, a DRAM refresh circuit 1424, a word line lowpotential generating circuit 1426, P-channel IGFET body bias potentialgenerating circuit 1428, N-channel IGFET body bias potential generatingcircuit 1430, output buffer circuit 1432, array potential generatingcircuit 1434, peripheral potential generating circuit 1436 and VPPgenerating circuit 1438.

Referring now to FIG. 15, a register circuit 1500 is set forth in acircuit schematic diagram.

There may be “m” register circuits 1500 comprising registers 1410 inoperational circuit 195.

Each register circuit 1500 may receive a predetermined one ofperformance parameters PP[m:1], load signal LOAD, and power up signalPUP at input terminals and may provide a corresponding latchedperformance parameter PPL[m:1] at an output terminal.

Each register circuit 1500 may include inverters (INV1502, INV1504, andINV1506), a passgate PG1502, and an N-channel IGFET N1502.

Pass gate PG1502 may receive one of performance parameters PP[m:1] aninput terminal 1502 at an input terminal and a load signal LOAD at acontrol input and may provide an output to an input of inverter INV1504.Inverter INV1502 may receive load signal LOAD and may provide an outputto another control input terminal of pass gate PG1502. N-channel IGFETN1502 may have a source connected to ground, a drain connected to theinput of inverter INV1504, and a gate connected to receive a power upsignal PUP. Inverter INV1504 may provide an latched performanceparameter PPL[m:1] to a terminal 1504. Inverter INV1506 may have aninput connected to terminal 1504 and an output connected to the input ofinverter INV1504 to form a latch.

The operation of register circuit 1500 will now be discussed. When aload operation occurs load signal LOAD pulses high. When load signalLOAD pulses high, the logic value at input node 1502 is passed throughpass gate PG1502 to be latched in cross-coupled inverters (INV1506 andINV1504) and provided as latched performance parameter PPL[m:1] atoutput terminal 1504. When load signal returns to a low logic level,pass gate PG1502 is turned off and the value remains latched incross-coupled inverters (INV1504 and INV1506). N-channel IGFET N1502 isprovided to supply a known default value to register circuit 1500 onpower up of semiconductor device 100. When power up occurs, power updetect signal PUP pulses high, thus turning on N-channel IGFET N1502 toprovide a low logic level input to inverter INV1504. In this way,latched performance parameter PPL[m:1] may be powered up to a knownstate.

Referring now to FIG. 16, a diagram of temperature ranges set bytemperature sensor circuits (120 and 130) according to an embodiment isset forth. The diagram of FIG. 16 illustrates the temperature rangesthat can correspond to each count value CNT[n:1]. Each temperature range(W1 to W2 ^(n), where n is the number of bits in count value CNT[n:1])can include a temperature range upper limit value (illustrated by asolid line) and an temperature range lower limit value (illustrated by adashed line). The temperature range upper limit value may be set by thecount value CNT[n:1] by the resistance value of variable resistor 310 intemperature sensor circuit 120. The temperature range lower limit valuemay be set by the count value CNT[n:1] by the resistance value ofvariable resistor 410 in temperature sensor circuit 130. It is notedthat each temperature range (W1 to W2 ^(n)) can overlap with an adjacenttemperature range (W1 to W2 ^(n)). For example, the temperature rangeupper limit value of temperature range W5 can overlap the temperaturerange lower limit value of temperature range W6 and the temperaturerange lower limit value of temperature range W5 can overlap thetemperature range upper limit value of temperature range W4. In otherwords, the temperature range upper limit value of temperature range W4and the temperature range lower limit value of temperature range W6 canboth fall within temperature range W5.

This overlap may be accomplished by selection of resistance values ofresistors (R300 and R400) or temperature sensor circuits (120 and 130).For example, resistor R300 may have a resistance value that is betweenR510-1 and 1.5 times R510-1 greater than resistor R400. In other words,the resistance value of resistor R300 may be between the resistancevalue of resistor R400 plus the resistance value of resistor R510-1 andthe resistance value of resistor R400 plus the 1.5 times the resistancevalue of resistor R510-1. Where resistor R510-1 has the resistance valueof R in the binary coded decimal scheme set forth for variable resistor500. In order to provide a more narrow overlap of temperature ranges,the resistance value of resistor R300 may be between the resistancevalue of resistor R400 plus the resistance value of resistor R510-1 andthe resistance value of resistor R400 plus the 1.1 times the resistancevalue of resistor R510-1.

The each respective value of count value CNT[n:1] can set resistancevalues of variable resistors (310 and 410) so that the increment signalINC may transition from a low logic level to a high logic level when thetemperature of the semiconductor device 100 transitions from within theset temperature range (W1 to W2 ^(n)) to the temperature range upperlimit value and so that the decrement signal DEC may transition from alow logic level to a high logic level when the temperature of thesemiconductor device 100 transitions from within the set temperaturerange (W1 to W2 ^(m)) to the temperature range lower limit value.

Having a unique value for the count value CNT[n:1] allows performanceparameters PP[m:1] to be latched as latched performance parametersPPL[m:1] and provided to performance parameter adjusted circuits 1420.In this way, performance parameter adjusted circuits 1420 mayfunctionally operate in each temperature range (W1 to W2 ^(n)) withoutthe necessity of providing undue margin at one temperature of operationin order to satisfy another temperature of operation.

Temperature ranges (W1 to W2 ^(n)) may be conceptualized as temperaturewindows.

Referring now to FIG. 17, a waveform diagram illustrating the power upoperation of semiconductor device 100 according to an embodiment is setforth.

The waveform diagram of FIG. 17 includes power supply Vext, power upsignal PUP, power up signal PUPD, increment signal INC, decrement signalDEC, count value CNT[5:1] (a 5-bit counter where n=5), count transitionsignal CTD, read signal READ, and load signal LOAD.

At an initial time, power may be turned off to semiconductor device 100and power supply Vext may be low. With power supply Vext all signals,including power up signal PUP, power up signal PUPD, increment signalINC, decrement signal DEC, count value CNT[n:1], count transition signalCTD, read signal READ, and load signal LOAD may be at a logic low level.

At time T1, semiconductor device 100 may be energized and power supplyVext may transition to a high level.

Due to the capacitive coupling in power up circuit 190, power up signals(PUP and PUPD) may transition from a logic low level to a logic highlevel.

In response to power up signal PUP being at a logic high level, countercircuit 140 may have the most significant bit CNT[5] of count valueCNT[5:1] preset to a logic high level and the other bits (CNT[4] toCNT[1]) of count value CNT[5:1] may be preset to a logic low level. Thepreset to a predetermined level may be accomplished in response to theconnection of power up signal PUP and ground potential to presetterminals PRE and clear terminals CLR of JK flip-flop circuits (710 a,710 b, and 710 c). In this way, count value CNT[5:1] may be preset to avalue of “10000” or essentially a midpoint of the ranges of values.

Also in response to power up signal PUP being a logic high level,temperature sensor circuits (120 and 130) may be disabled and incrementsignal INC and decrement signal DEC may be forcibly set to a logic lowlevel.

In temperature sensor circuit 120 (FIG. 3), logic gate G300 may receivepower up signal PUP having a logic high level. Because logic gate G300is a NOR gate, the output of logic gate G300 may be low. In this way,the n-channel IGFET 310 and p-channel IGFET P310 of passgate PG300 mayrespectively receive a logic low level and logic high level and passgatePG300 may be turned off and in a high impedance state. N-channel IGFETN300 may receive a logic high level and may be turned on to provide alow impedance path from the output terminal producing increment signalINC and a ground potential. In this way increment signal INC may beforcibly set to a logic low level.

In temperature sensor circuit 130 (FIG. 4), logic gate G400 may receivepower up signal PUP having a logic high level. Because logic gate G400is a NOR gate, the output of logic gate G400 may be low. In this way,the n-channel IGFET N410 and p-channel IGFET P410 of passgate PG400 mayrespectively receive a logic low level and logic high level and passgatePG400 may be turned off and in a high impedance state. N-channel IGFETN400 may receive a logic high level and may be turned on to provide alow impedance path from the output terminal producing decrement signalDEC and a ground potential. In this way decrement signal DEC may beforcibly set to a logic low level.

Also at this time, each of the m register circuits 1500 (FIG. 15) mayreceive power up signal PUP at the gate of n-channel IGFET N1502. Withpower up signal PUP at a logic high, n-channel IGFET N1502 may provide alow impedance path between the input of inverter INV1504 and ground. Inthis way, each latched performance parameter PPL[m:1] may be forced to alogic high level during power up.

At time T2, after charge node N1 in power up circuit 190 (FIG. 11)reaches a trip point of inverter logic gate G1122 and propagates throughseries connected inverter/capacitor chain (G1122-C1122, G1124-C1124,G1126-C1126, C1128, and C1129), power up signal PUP may transition to alogic low level.

With power up signal PUP at a logic low level, temperature sensorcircuits (120 and 130) may be enabled.

In temperature sensor circuit 120 (FIG. 3), logic gate G300 may receivepower up signal PUP, count limit signal MAX, and count transition signalCTD having low logic levels. With all inputs at a low logic level, NORlogic gate G300 may provide a logic high output. In this way, then-channel IGFET N310 and p-channel IGFET P310 of passgate PG300 mayrespectively receive a logic high level and logic low level and passgatePG300 may be turned on and provide a low impedance between the output ofamplifier circuit AMP300 and output terminal providing increment signalINC. N-channel IGFET N300 may receive a logic low level and may beturned off to provide a high impedance path from the output terminalproducing increment signal INC and a ground potential.

In temperature sensor circuit 130 (FIG. 4), logic gate G400 may receivepower up signal PUP, count limit signal MIN, and count transition signalCTD having low logic levels. With all inputs at a low logic level, NORlogic gate G400 may provide a logic high output. In this way, then-channel IGFET N410 and p-channel IGFET P410 of passgate PG400 mayrespectively receive a logic high level and logic low level and passgatePG400 may be turned on and provide a low impedance between the output ofinverter logic gate G420 and output terminal providing decrement signalDEC. N-channel IGFET N400 may receive a logic low level and may beturned off to provide a high impedance path from the output terminalproducing decrement signal DEC and a ground potential.

At this time, count value CNT[5:1] has a value of “10000” to set thetemperature range as temperature range W33 as an initial condition inpower up. However, the temperature of semiconductor device 100 may beoutside temperature range W33. In this particular power up example, thetemperature of semiconductor device 100 may be within temperature rangeW39.

Therefore, once temperature sensor circuits (120 and 130) are enabled,temperature sensor circuit 130 may detect a temperature above the upperlimit value of temperature range W32. In this way, shortly after timeT2, increment signal INC may transition from a logic low level to alogic high level. Counter circuit 140 (FIG. 6) may receive the logichigh increment signal INC. Counter cell CS1 may receive increment signalINC at a count up input terminal CUIN. A time delay later (determined byinverting delay stage INVD), increment signal INC may propagate toprovide a high logic level at the clock input CLK of all the counterstages (CS1 to CS5). Because the least significant bit CNT[1] of countvalue CNT[5:1] is at a logic low level, only the least significant bitCNT[1] may toggle in response to receiving a high logic level at theclock input CLK. In this way, the count value CNT[5:1] may transitionfrom “10000” to “10001”.

Count transition detector 160 (FIG. 9) may provide a high going pulse ascount transition signal CTD in response to the transition of leastsignificant bit CNT[1] of count value CNT[5:1].

Temperature sensors circuits (120 and 130) may receive the high goingpulse of count transition signal CTD.

In temperature sensor circuit 120 (FIG. 3), logic gate G300 may receivecount transition signal CTD having a logic high level. Because logicgate G300 is a NOR gate, the output of logic gate G300 may be low. Inthis way, the n-channel IGFET 310 and p-channel IGFET P310 of passgatePG300 may respectively receive a logic low level and logic high leveland passgate PG300 may be turned off and in a high impedance state.N-channel IGFET N300 may receive a logic high level and may be turned onto provide a low impedance path from the output terminal producingincrement signal INC and a ground potential. In this way incrementsignal INC may be forcibly set to a logic low level. Therefore,increment signal INC transitions to a logic low level, in response tocount transition signal CTD transitioning to a logic high level andtemperature sensor circuit 120 may be disabled during the period inwhich count transition signal CTD is at a logic high level. In a similarmanner temperature sensor circuit 130 may be disabled during the periodin which count transition signal CTD is at a logic high level.

Temperature sensor circuits (120 and 130) may receive count valueCNT[5:1] having a value of “10001” at the input of variable resistors(310 and 410). In this way, when count transition signal CTD transitionsto a low logic level, the temperature sensor circuits (120 and 130) maybe set to a temperature range W34.

Because the temperature of semiconductor device 100 is above the upperlimit value of temperature range W34, temperature sensor circuit 130 maydetect a temperature above the upper limit value of temperature rangeW34. In this way, shortly after time T3, increment signal INC maytransition from a logic low level to a logic high level. In response toincrement signal INC transitioning, count value CNT[5:1] may incrementfrom “10001” to “10010” in a manner described above and the temperaturerange may be set to temperature range W35.

Because the temperature of semiconductor device 100 is above the upperlimit value of temperature range W35, temperature sensor circuit 130 maydetect a temperature above the upper limit value of temperature rangeW35. In this way, shortly after time T3, increment signal INC maytransition from a logic low level to a logic high level. In response toincrement signal INC transitioning, count value CNT[5:1] may incrementfrom “10010” to “10011” in a manner described above and the temperaturerange may be set to temperature range W36.

This procedure may be repeated at times T5, T6, and T7 until the countvalue CNT[5:1] becomes “10110” and the temperature range is set totemperature range W39 which is the range in which the actual temperatureof semiconductor device 100 may be currently operating.

At time T8, the power up circuit 190 (FIG. 11) may produce a power uppulse PUPD that transitions from a logic high to a logic low level. Inresponse to this transition, control circuit 180 (FIG. 10) may provide aread pulse having essentially the pulse width of the propagation time ofdelay circuit D1012. Performance parameter table 170 (FIG. 12) mayreceive the read signal and may provide performance parameters (PP1 toPPm) in accordance with the word line (WL1 to WLx) activated by countvalue CNT[5:1] having a value of “10110”.

After a delay time that is essentially the propagation delay of delaycircuit D1032, control circuit 180 may provide a high going pulse forload signal LOAD having a pulse width that is essentially thepropagation delay of delay circuit D1034. In this way, performanceparameters PP[m:1] may be latched into register circuits 1500 to providelatched performance parameters PPL[m:1]. At this time the power upprocedure may be completed and the performance parameter adjustedcircuits 1420 may be optimized for operating in a temperature range W39(i.e. the temperature in which semiconductor device 100 is currentlyafter power up).

By initializing counter 140 to have a count value near the midpoint ofthe allowed temperature operating range of semiconductor device 100, thespecific operating range among all operating ranges for temperaturesensing circuits (120 to 130) may be set without undue toggling of countvalue CNT[5:1] and thereby unduly wasting current.

Referring now to FIG. 18, a waveform diagram illustrating a detection ofan increase in temperature from a first temperature range to a secondtemperature range is set forth.

The waveform diagram of FIG. 18 includes increment signal INC, decrementsignal DEC, count value CNT[5:1] (a 5-bit counter), count transitionsignal CTD, read signal READ, load signal LOAD, performance parametersPP[m:1], and latched performance parameters PPL[m:1]).

Initially, the temperature of semiconductor device 100 may be in a firsttemperature range established by count value CNT[5:1]=10000. At thistime, read signal READ may be at a logic low level and precharge circuit1220 (FIG. 13) may provide a low impedance path between power supply VDDand each column line providing performance parameters PP[m:1] (eachp-channel IGFET P1300 may be turned on). In this way, each column linemay be precharged to a logic high level (essentially power supply VDD).

At time T1, temperature sensor circuit 120 (FIG. 3) may detect anincrease in temperature of semiconductor device 100 to the uppertemperature range upper limit value (the range established by countvalue CNT[5:1]=10000). In response to this temperature increase,increment signal INC may transition to a logic high level. Countercircuit 140 (FIG. 6) may receive the logic high increment signal INC.Counter cell CS1 may receive increment signal INC at a count up inputterminal CUIN. A time delay later (determined by inverting delay stageINVD), increment signal INC may propagate to provide a high logic levelat the clock input CLK (counter clock CLK) of all the counter stages(CS1 to CS5). Because the least significant bit CNT[1] of count valueCNT[5:1] is at a logic low level, only the least significant bit CNT[1]may toggle in response to receiving a high logic level at the clockinput CLK. In this way, the count value CNT[5:1] may transition from“10000” to “10001”. It should be noted inverting delay stage INVD isprovided to ensure that count up signals (CUP1 to CUP4) have propagatedthrough the entire chain of counter stages (CS1 to CS5) before thecounter stages are clocked by counter clock CCLK.

Count transition detector 160 (FIG. 9) may provide a high going pulse ascount transition signal CTD in response to the transition of leastsignificant bit CNT[1] of count value CNT[5:1]. The count transitionsignal may have a pulse width Δt1 that is essentially the propagationdelay of delay circuit D910.

Temperature sensors circuits (120 and 130) may receive the high goingpulse of count transition signal CTD and increment signal INC may beforcibly set to a logic low level in response to count transition signalCTD as previously described.

Temperature sensor circuits (120 and 130) may receive count valueCNT[5:1] having a value of “10001” at the input of variable resistors(310 and 410). In this way, when count transition signal CTD transitionsto a low logic level, the temperature sensor circuits (120 and 130) maybe set to a temperature range as determined by count value CNT[5:1]having a value of “10001”.

In response to count transition signal CTD pulse, read signal generatingcircuit 1010 in control circuit 1010 (FIG. 10) may provide a read signalREAD having a high going pulse that essentially has the same pulse widthΔt1 as count transitions signal CTD.

When read signal READ goes high, precharge circuit 1220 (FIG. 12 andFIG. 13) may be disabled (each p-channel IGFET P1300 may be turned off)and a high impedance path may be provided between power supply VDD andeach column line providing performance parameters PP[m:1].

Row selection circuit 1210 (FIG. 12) may be enabled by read signal READto activate a predetermined word line (WL1 to WLx, where x=2^(n)) inresponse to the value (10001) of count value (CNT[1] to CNT[n]). In thisway, each column line may be driven by a selected memory cell MC toprovide performance parameters PP[m:1].

After a delay time that is essentially the propagation delay of delaycircuit D1032, control circuit 180 (FIG. 10) may provide a high goingpulse for load signal LOAD having a pulse width Δt2 that is essentiallythe propagation delay of delay circuit D1034. In this way, performanceparameters PP[m:1] may be latched into register circuits 1500 to providelatched performance parameters PPL[m:1].

Referring now to FIG. 19, a waveform diagram illustrating a detection ofa decrease in temperature from a first temperature range to a secondtemperature range is set forth.

The waveform diagram of FIG. 19 includes increment signal INC, decrementsignal DEC, count value CNT[5:1] (a 5-bit counter), count transitionsignal CTD, read signal READ, load signal LOAD, performance parametersPP[m:1], and latched performance parameters PPL[m:1]).

The operation of decreasing from a first temperature range to a secondtemperature range is essentially the same as increasing from a firsttemperature range to a second temperature range as described withrespect to FIG. 18 above except temperature sensor circuit 130 providesa decrement signal DEC to counter circuit 140 and counter may toggle allbits of count value CNT[5:1] due to the propagation of count downsignals (CDN1 to CDN4) providing logic high levels indicating counterstages (CS1 to CS5) are to toggle bits of count value CNT[5:1]. In thisway, the count value CNT[5:1] may transition from “10000” to “01111” andthe temperature sensor circuits (120 and 130) may be set to atemperature range as determined by count value CNT[5:1] having a valueof “01111”.

Referring now to FIG. 20, a waveform diagram illustrating the operationof semiconductor device 100 over various temperature ranges.

The waveform diagram of FIG. 20 includes a temperature waveformTemperature, increment signal INC, decrement signal DEC, count valueCNT[5:1] (indicating a 5-bit counter 140), count transition signal CTD,read signal READ, load signal LOAD, performance parameters PP[m:1], andlatched performance parameters PPL[m:1].

The temperature Temperature illustrated in the waveform diagram of FIG.20 includes three temperature ranges (W33, W34, and W35). Temperaturerange W33 includes a temperature range lower limit value 2002 and atemperature range upper limit value 2006. Temperature range W34 includesa temperature range lower limit value 2004 and a temperature range upperlimit value 2010. Temperature range W35 includes a temperature rangelower limit value 2008 and a temperature range upper limit value 2012.It should be noted that temperature range W34 overlaps a portion of bothadjacent temperature ranges (W33 and W35).

Initially, semiconductor device 100 may be operating in a temperaturerange W33 as set by count value CNT[5:1] having a value of “10000”.Temperature range W33 may have a temperature range lower limit value2002 and a temperature range upper limit value 2006. At this timelatched performance parameters PPL[m:1] may have a value (shown asPPL-W33) for operating within temperature range W33.

At time T1, the temperature of semiconductor device 100 can reach thetemperature range upper limit value 2006 and temperature sensor circuit120 (FIG. 3) may provide an increment signal INC that transitions from alow logic level to a high logic level. Count value CNT[5:1] may beincremented in response to increment signal INC to provide a count valueCNT[5:1] having a value of “10001”. Count transition signal CTD maydetect a transition in the least significant bit CNT[1] of count valueCNT[5:1] to provide a high going pulse. Read signal READ may begenerated in response to count transition signal. In this way,performance parameters PP[m:1] may be provided. Load signal LOAD may begenerated in response to read signal READ and performance parameterPP[m:1] may be latched to provide latched performance parametersPPL[5:1].

At this time latched performance parameters PPL[m:1] may have a value(shown as PPL-W34) for operating within temperature range W34.Temperature range W34 may have a temperature range lower limit value2004 and a temperature range upper limit value 2010. The temperaturerange lower limit value 2004 of temperature range W34 may be at a lowertemperature than the temperature range upper limit value 2006 oftemperature range W33. In this way, temperature ranges (W33 and W34) mayoverlap. The temperature range lower limit value 2008 of temperaturerange W35 may be at a lower temperature than the temperature range upperlimit value 2010 of temperature range W34. In this way, temperatureranges (W34 and W35) may overlap.

At time T2, the temperature of semiconductor device 100 can reach thetemperature range upper limit value 2010 and temperature sensor circuit120 (FIG. 3) may provide a increment signal INC that transitions from alow logic level to a high logic level. Count value CNT[5:1] may beincremented in response to increment signal INC to provide a count valueCNT[5:1] having a value of “10010”. Count transition signal CTD maydetect a transition in the least significant bit CNT[1] of count valueCNT[5:1] to provide a high going pulse. Read signal READ may begenerated in response to count transition signal. In this way,performance parameters PP[m:1] may be provided. Load signal LOAD may begenerated in response to read signal READ and performance parameterPP[m:1] may be latched to provide latched performance parametersPPL[5:1].

At this time, latched performance parameters PPL[m:1] may have a value(shown as PPL-W35) for operating within temperature range W35.Temperature range W35 may have a temperature range lower limit value2008 and a temperature range upper limit value 2012. The temperaturerange lower limit value 2008 of temperature range W35 may be at a lowertemperature than the temperature range upper limit value 2010 oftemperature range W34. In this way, temperature ranges (W34 and W35) mayoverlap.

At time T3, the temperature of semiconductor device 100 can reach thetemperature range lower limit value 2008 and temperature sensor circuit130 (FIG. 3) may provide a decrement signal DEC that transitions from alow logic level to a high logic level. Count value CNT[5:1] may bedecremented in response to decrement signal DEC to provide a count valueCNT[5:1] having a value of “10001”. Count transition signal CTD maydetect a transition in the least significant bit CNT[1] of count valueCNT[5:1] to provide a high going pulse. Read signal READ may begenerated in response to count transition signal. In this way,performance parameters PP[m:1] may be provided. Load signal LOAD may begenerated in response to read signal READ and performance parameterPP[m:1] may be latched to provide latched performance parametersPPL[5:1].

At this time, latched performance parameters PPL[m:1] may have a value(shown as PPL-W34) for operating within temperature range W34.

At time T4, the temperature of semiconductor device 100 can once againreach the temperature range upper limit value 2010 and temperaturesensor circuit 120 (FIG. 3) may provide a increment signal INC thattransitions from a low logic level to a high logic level. Count valueCNT[5:1] may be incremented in response to increment signal INC toprovide a count value CNT[5:1] having a value of “10010”. Counttransition signal CTD may detect a transition in the least significantbit CNT[1] of count value CNT[5:1] to provide a high going pulse. Readsignal READ may be generated in response to count transition signal. Inthis way, performance parameters PP[m:1] may be provided. Load signalLOAD may be generated in response to read signal READ and performanceparameter PP[m:1] may be latched to provide latched performanceparameters PPL[5:1].

At this time, latched performance parameters PPL[m:1] may have a value(shown as PPL-W35) for operating within temperature range W35.

Referring now to FIG. 21, a waveform diagram illustrating the operationof semiconductor device 100 over various temperature ranges near amaximum temperature range.

The waveform diagram of FIG. 21 includes a temperature waveformTemperature, increment signal INC, decrement signal DEC, count valueCNT[5:1] (indicating a 5-bit counter 140), count transition signal CTD,read signal READ, load signal LOAD, performance parameters PP[m:1],latched performance parameters PPL[m:1], and count limit signal MAX.

The temperature Temperature illustrated in the waveform diagram of FIG.21 includes two temperature ranges (W63 and W64). Temperature range W63includes a temperature range lower limit value 2102 and a temperaturerange upper limit value 2106. Temperature range W64 includes atemperature range lower limit value 2104 and a temperature range upperlimit value 2108.

Initially, semiconductor device 100 may be operating in a temperaturerange W63 as set by count value CNT[5:1] having a value of “11110”. Atthis time, latched performance parameters PPL[m:1] may have a value(shown as PPL-W63) for operating within temperature range W63.

At time T1, the temperature of semiconductor device 100 can reach thetemperature range upper limit value 2106 and temperature sensor circuit120 (FIG. 3) may provide a increment signal INC that transitions from alow logic level to a high logic level. Count value CNT[5:1] may beincremented in response to increment signal INC to provide a count valueCNT[5:1] having a value of “11111”. Count transition signal CTD maydetect a transition in the least significant bit CNT[1] of count valueCNT[5:1] to provide a high going pulse. Read signal READ may begenerated in response to count transition signal. In this way,performance parameters PP[m:1] may be provided. Load signal LOAD may begenerated in response to read signal READ and performance parameterPP[m:1] may be latched to provide latched performance parametersPPL[5:1].

At this time latched performance parameters PPL[m:1] may have a value(shown as PPL-W64) for operating within temperature range W64.Temperature range W64 may have a temperature range lower limit value2104 and a temperature range upper limit value 2108.

Also, at this time maximum count limit circuit 800 a (FIG. 8) of countlimit detector 150 may provide a count limit signal MAX that transitionsto a high logic level in response to count value[5:1] having a value of“11111”.

In temperature sensor circuit 120 (FIG. 3), logic gate G300 may receivecount limit signal MAX having a logic high level. Because logic gateG300 is a NOR gate, the output of logic gate G300 may be low. In thisway, the n-channel IGFET 310 and p-channel IGFET P310 of passgate PG300may respectively receive a logic low level and logic high level andpassgate PG300 may be turned off and in a high impedance state.N-channel IGFET N300 may receive a logic high level and may be turned onto provide a low impedance path from the output terminal producingincrement signal INC and a ground potential. In this way, incrementsignal INC may be forcibly set to a logic low level. Therefore,temperature sensor circuit 120 may be disabled in response to countlimit signal MAX being at a logic high level.

At time T2, the temperature of semiconductor device 100 can reach thetemperature range upper lower value 2108. However, because count limitsignal MAX is at a logic high level, increment signal INC remains at alogic low level. Therefore, count value CNT[5:1] can retain a value of“11111” and latched performance parameters PPL[m:1] may retain a value(shown as PPL-W64) for operating within temperature range W64. Countlimit signal MAX operates to prevent counter 140 from rolling over to acount of “00000” from “11111”. The performance parameters PPL-W64corresponding to a count value of “11111” may be set to provide areasonable margin to allow semiconductor device 100 to continue tooperate at high temperatures beyond temperature range W64.

At time T3, the temperature of semiconductor device 100 can reach thetemperature range lower limit value 2104 and temperature sensor circuit130 (FIG. 4) may provide a decrement signal DEC that transitions from alow logic level to a high logic level. Count value CNT[5:1] may bedecremented in response to decrement signal DEC to provide a count valueCNT[5:1] having a value of “11110”. Count transition signal CTD maydetect a transition in the least significant bit CNT[1] of count valueCNT[5:1] to provide a high going pulse. Read signal READ may begenerated in response to count transition signal. In this way,performance parameters PP[m:1] may be provided. Load signal LOAD may begenerated in response to read signal READ and performance parameterPP[m:1] may be latched to provide latched performance parametersPPL[5:1].

At this time, latched performance parameters PPL[m:1] may have a value(shown as PPL-W63) for operating within temperature range W63.

At time T4, the temperature of semiconductor device 100 can once againreach the temperature range upper limit value 2106 and temperaturesensor circuit 120 (FIG. 3) may provide a increment signal INC thattransitions from a low logic level to a high logic level. Count valueCNT[5:1] may be incremented in response to increment signal INC toprovide a count value CNT[5:1] having a value of “11111”. Counttransition signal CTD may detect a transition in the least significantbit CNT[1] of count value CNT[5:1] to provide a high going pulse. Readsignal READ may be generated in response to count transition signal. Inthis way, performance parameters PP[m:1] may be provided. Load signalLOAD may be generated in response to read signal READ and performanceparameter PP[m:1] may be latched to provide latched performanceparameters PPL[5:1].

At this time latched performance parameters PPL[m:1] may have a value(shown as PPL-W64) for operating within temperature range W64.Temperature range W64 may have a temperature range lower limit value2104 and a temperature range upper limit value 2108.

Also, at this time maximum count limit circuit 800 a (FIG. 8) of countlimit detector 150 may once again provide a count limit signal MAX thattransitions to a high logic level in response to count value[5:1] havinga value of “11111”. At this time temperature sensor circuit 120 may onceagain be disabled in response to count limit signal MAX having a highlogic level so that counter 140 may not roll over from a count valueCNT[5:1] of “11111” to “00000” in response to an undesired incrementsignal INC.

Referring now to FIG. 22, a waveform diagram illustrating the operationof semiconductor device 100 over various temperature ranges near aminimum temperature range.

The waveform diagram of FIG. 22 includes a temperature waveformTemperature, increment signal INC, decrement signal DEC, count valueCNT[5:1] (indicating a 5-bit counter 140), count transition signal CTD,read signal READ, load signal LOAD, performance parameters PP[m:1],latched performance parameters PPL[m:1], and count limit signal MIN.

The temperature Temperature illustrated in the waveform diagram of FIG.22 includes two temperature ranges (W1 and W2). Temperature range W1includes a temperature range lower limit value 2202 and a temperaturerange upper limit value 2206. Temperature range W2 includes atemperature range lower limit value 2204 and a temperature range upperlimit value 2208.

Initially, semiconductor device 100 may be operating in a temperaturerange W2 as set by count value CNT[5:1] having a value of “00001”. Atthis time, latched performance parameters PPL[m:1] may have a value(shown as PPL-W2) for operating within temperature range W2.

At time T1, the temperature of semiconductor device 100 can reach thetemperature range lower limit value 2204 and temperature sensor circuit130 (FIG. 4) may provide a decrement signal DEC that transitions from alow logic level to a high logic level. Count value CNT[5:1] may bedecremented in response to increment signal DEC to provide a count valueCNT[5:1] having a value of “00000”. Count transition signal CTD maydetect a transition in the least significant bit CNT[1] of count valueCNT[5:1] to provide a high going pulse. Read signal READ may begenerated in response to count transition signal. In this way,performance parameters PP[m:1] may be provided. Load signal LOAD may begenerated in response to read signal READ and performance parameterPP[m:1] may be latched to provide latched performance parametersPPL[5:1].

At this time latched performance parameters PPL[m:1] may have a value(shown as PPL-W1) for operating within temperature range W1. Temperaturerange W1 may have a temperature range lower limit value 2202 and atemperature range upper limit value 2206.

Also, at this time minimum count limit circuit 800 b (FIG. 8) of countlimit detector 150 may provide a count limit signal MIN that transitionsto a high logic level in response to count value[5:1] having a value of“00000”.

In temperature sensor circuit 130 (FIG. 4), logic gate G400 may receivecount limit signal MIN having a logic high level. Because logic gateG400 is a NOR gate, the output of logic gate G400 may be low. In thisway, the n-channel IGFET 410 and p-channel IGFET P410 of passgate PG400may respectively receive a logic low level and logic high level andpassgate PG400 may be turned off and in a high impedance state.N-channel IGFET N400 may receive a logic high level and may be turned onto provide a low impedance path from the output terminal producingdecrement signal DEC and a ground potential. In this way, decrementsignal DEC may be forcibly set to a logic low level. Therefore,temperature sensor circuit 130 may be disabled in response to countlimit signal MIN being at a logic high level.

At time T2, the temperature of semiconductor device 100 can reach thetemperature range lower limit value 2202. However, because count limitsignal MIN is at a logic high level, decrement signal DEC remains at alogic low level. Therefore, count value CNT[5:1] can retain a value of“00000” and latched performance parameters PPL[m:1] may retain a value(shown as PPL-W1) for operating within temperature range W1. Count limitsignal MIN operates to prevent counter 140 from rolling over to a countof “11111” from “00000”. The performance parameters PPL-W1 correspondingto a count value of “00000” may be set to provide a reasonable margin toallow semiconductor device 100 to continue to operate at hightemperatures below temperature range W1.

At time T3, the temperature of semiconductor device 100 can reach thetemperature range upper limit value 2206 and temperature sensor circuit120 (FIG. 3) may provide a increment signal INC that transitions from alow logic level to a high logic level. Count value CNT[5:1] may beincremented in response to decrement signal INC to provide a count valueCNT[5:1] having a value of “00001”. Count transition signal CTD maydetect a transition in the least significant bit CNT[1] of count valueCNT[5:1] to provide a high going pulse. Read signal READ may begenerated in response to count transition signal. In this way,performance parameters PP[m:1] may be provided. Load signal LOAD may begenerated in response to read signal READ and performance parameterPP[m:1] may be latched to provide latched performance parametersPPL[5:1].

At this time, latched performance parameters PPL[m:1] may have a value(shown as PPL-W2) for operating within temperature range W2.

At time T4, the temperature of semiconductor device 100 can once againreach the temperature range lower limit value 2204 and temperaturesensor circuit 130 (FIG. 4) may provide a decrement signal DEC thattransitions from a low logic level to a high logic level. Count valueCNT[5:1] may be decremented in response to increment signal DEC toprovide a count value CNT[5:1] having a value of “00000”. Counttransition signal CTD may detect a transition in the least significantbit CNT[1] of count value CNT[5:1] to provide a high going pulse. Readsignal READ may be generated in response to count transition signal. Inthis way, performance parameters PP[m:1] may be provided. Load signalLOAD may be generated in response to read signal READ and performanceparameter PP[m:1] may be latched to provide latched performanceparameters PPL[5:1].

At this time latched performance parameters PPL[m:1] may have a value(shown as PPL-W1) for operating within temperature range W1. Temperaturerange W1 may have a temperature range lower limit value 2202 and atemperature range upper limit value 2206.

Also, at this time minimum count limit circuit 800 b (FIG. 8) of countlimit detector 150 may once again provide a count limit signal MIN thattransitions to a high logic level in response to count value[5:1] havinga value of “00000”. At this time temperature sensor circuit 130 may onceagain be disabled in response to count limit signal MIN having a highlogic level so that counter 140 may not roll over from a count valueCNT[5:1] of “00000” to “11111” in response to an undesired decrementsignal DEC.

Referring now to FIG. 23, a semiconductor device according to anembodiment is set forth in a block schematic diagram and given thegeneral reference character 2300.

Semiconductor device 2300 may include similar constituents andsemiconductor device 100. Such constituents may be given the samereference character and a description of such may be omitted.Semiconductor device 2300 may differ from semiconductor device 100 inthat temperature sensor circuit 2300 may be included instead oftemperature sensor circuits (120 and 130). Semiconductor device 2300 mayfurther include a selection circuit 2320.

Temperature sensor circuit 2310 may receive reference voltages(V_(BGREF) and V_(TEMP)), count limit signals (MIN and MAX), counttransition signal CTD, power up signal PUP, count value CNT[n:1], and aselection signal ISEL as inputs and may provide an increment signal INCand a decrement signal DEC as outputs.

Selection circuit 2320 may be an oscillator circuit that providesselection signal ISEL as a signal that oscillates between a first logiclevel and a second logic level. Selection signal may have an oscillationtime period.

Semiconductor device 2300 may operate essentially the same assemiconductor device 100 except that temperature sensor circuit 2310 mayalternate between being enabled to detect the temperature range upperlimit value and the temperature range lower limit value in response tothe logic state of selection signal ISEL. In particular, when selectionsignal ISEL has a high logic level, temperature sensor circuit 2310 maybe enabled to detect the temperature range upper limit value and whenselection signal ISEL has a low logic level, temperature sensor circuit2310 may be enabled to detect the temperature range lower limit value.

Referring now to FIG. 24, a circuit schematic diagram of temperaturesensor circuit 2310 according to an embodiment is set forth.

Temperature sensor circuit 2310 may receive reference voltages(V_(BGREF) and V_(TEMP)), count limit signals (MIN and MAX), counttransition signal CTD, power up signal PUP, count value CNT[n:1], and aselection signal ISEL as inputs and may provide an increment signal INCand a decrement signal DEC as outputs.

Temperature sensor circuit 2310 can include a temperature sensingportion 2410, an increment signal output portion 2420, and a decrementsignal output portion 2430. Temperature sensing portion 2410 can receivereference voltages (V_(BGREF) and V_(TEMP)), count value CNT[n:1], and aselection signal ISEL as inputs and may provide an temperature detectsignal TD3 as an output. Increment signal output portion 2420 mayreceive temperature detect signal TD3, count limit signal MAX, counttransition signal CTD, power up signal PUP, and selection signal ISEL asinputs and may provide an increment signal INC as an output. Decrementsignal output portion 2430 may receive temperature detect signal TD3,count limit signal MIN, count transition signal CTD, power up signalPUP, and selection signal ISEL as inputs and may provide a decrementsignal DEC as an output.

Temperature sensing portion 2410 can include a p-channel insulated gatefield effect transistor (IGFET) P2400, a variable resistor 2412,resistors (R2400 and R2420), n-channel IGFET N2400, and an amplifierAMP2400.

P-channel IGFET P2400 may have a source terminal connected to a powersupply potential VDD, a drain commonly connected to a first terminal ofvariable resistor 2412 and a positive input terminal of amplifierAMP2400 at node ND24, and a gate terminal connected to receive voltageV_(TEMP). The potential of voltage V_(TEMP) may change inversely to thechange in the temperature of the semiconductor device 100. Variableresistor 2412 may receive count value CNT[n:1] as inputs and may have asecond terminal connected to a first terminal of resistor R2400 and adrain of n-channel IGFET N2400. Resistor R2400 may have a secondterminal connected to a first terminal of resistor R2400 and a sourceterminal of n-channel IGFET N2400. N-channel IGFET N2400 may have a gateterminal connected to receive selection signal ISEL. N-channel IGFETN2400 may provide a shunt for resistor R240 in response to selectionsignal ISEL. Resistor R2400 may have a second terminal connected toground a potential. Amplifier AMP2400 may have a negative input terminalconnected to receive voltage V_(BGREF) and an output terminal connectedto provide temperature detect signal TD3. Voltage V_(BGREF) may not varywith temperature and may have an essentially constant potential.

Increment signal output portion 2420 may include inverter logic gates(G2422 and G2426), NOR logic gate G2424, pass gate PG2420, and n-channelIGFET N2422.

Inverter logic gate G2422 may receive selection signal ISEL at an inputterminal and may provide an output. NOR logic gate G2424 may receive theoutput of inverter logic gate G2422, count limit signal MAX, power upsignal PUP, and count transition signal CTD as inputs and may provide anoutput. Inverter logic gate G2426 may receive the output of NOR logicgate G2424 at an input terminal and may provide an output. Pass gatePG2420 may receive the output of NOR logic gate G2424 and inverter logicgate G2426 as inputs and may provide a controllable impedance pathbetween temperature detect signal TD3 and the increment signal INC.N-channel IGFET N2422 may have a drain terminal connected to incrementsignal INC, a source connected to a ground potential and a gate terminalconnected to receive the output of inverter logic gate G2426.

Pass gate PG2420 may include an n-channel IGFET N2420 and a p-channelIGFET P2420 having source/drain terminals connected in parallel betweentemperature detect signal TD3 and an output terminal to provideincrement signal INC. N-channel IGFET N2420 may receive the output ofNOR logic gate G2424 at a gate terminal. P-channel IGFET P2420 mayreceive the output of inverter logic gate G2426 at a gate terminal. Inthis way, pass gate PG2420 may provide a controllable impedance pathbetween the temperature detect signal TD3 and increment signal INC inresponse to the output of NOR logic gate G2424.

Decrement signal output portion 2430 may include inverter logic gates(G2432 and G2436), NOR logic gate G2434, pass gate PG2430, and n-channelIGFET N2432.

Inverter logic gate G2432 may receive temperature detect signal TD3 atan input terminal and may provide an output. NOR logic gate G2434 mayreceive the selection signal ISEL, count limit signal MAX, power upsignal PUP, and count transition signal CTD as inputs and may provide anoutput. Inverter logic gate G2436 may receive the output of NOR logicgate G2434 at an input terminal and may provide an output. Pass gatePG2430 may receive the output of NOR logic gate G2434 and inverter logicgate G2436 as inputs and may provide a controllable impedance pathbetween the output of inverter logic gate 2432 and the decrement signalDEC. N-channel IGFET N2432 may have a drain terminal connected todecrement signal DEC, a source connected to a ground potential and agate terminal connected to receive the output of inverter logic gateG2436.

Pass gate PG2430 may include an n-channel IGFET N2430 and a p-channelIGFET P2430 having source/drain terminals connected in parallel betweenthe output of inverter logic gate 2432 and the decrement signal DEC.N-channel IGFET N2430 may receive the output of NOR logic gate G2434 ata gate terminal. P-channel IGFET P2430 may receive the output ofinverter logic gate G2436 at a gate terminal. In this way, pass gatePG2430 may provide a controllable impedance path between the output ofinverter logic gate 2432 and the decrement signal DEC. in response tothe output of NOR logic gate G2434.

Variable resistor 500 of FIG. 5 may be used as variable resistor 2412.Resistor R2420 may be selected to have a value that is between theresistance value of R510-1 and 1.5 times the resistance value of R510-1.In order to provide a more narrow overlap of temperature ranges,resistor R2420 may be selected to have a value that is between theresistance value of R510-1 and 1.1 times the resistance value of R510-1.

Referring now to FIG. 25, a waveform diagram illustrating the operationof semiconductor device 2300 over various temperature ranges.

The waveform diagram of FIG. 25 includes a temperature waveformTemperature, selection signal ISEL, increment signal INC, decrementsignal DEC, count value CNT[5:1] (indicating a 5-bit counter 140), counttransition signal CTD, performance parameters PP[m:1], and latchedperformance parameters PPL[m:1].

The temperature Temperature illustrated in the waveform diagram of FIG.25 includes three temperature ranges (W33, W34, and W35). Temperaturerange W33 includes a temperature range lower limit value 2502 and atemperature range upper limit value 2506. Temperature range W34 includesa temperature range lower limit value 2504 and a temperature range upperlimit value 2510. Temperature range W35 includes a temperature rangelower limit value 2508 and a temperature range upper limit value 2512.It should be noted that temperature range W34 overlaps a portion of bothadjacent temperature ranges (W33 and W35).

Initially, semiconductor device 2300 may be operating in a temperaturerange W33 as set by count value CNT[5:1] having a value of “10000”.Temperature range W33 may have a temperature range lower limit value2502 and a temperature range upper limit value 2506. At this timelatched performance parameters PPL[m:1] may have a value (shown asPPL-W33) for operating within temperature range W33.

Selection signal ISEL may be an oscillating signal generated byselection circuit 2320. Temperature sensor circuit 2310 may alternatebetween being enabled to detect the temperature range upper limit valueand the temperature range lower limit value in response to the logicstate of selection signal ISEL. In particular, when selection signalISEL has a high logic level, temperature sensor circuit 2310 may beenabled to detect the temperature range upper limit value and whenselection signal ISEL has a low logic level, temperature sensor circuit2310 may be enabled to detect the temperature range lower limit value.Selection signal ISEL may have an oscillation time period Td.Oscillation time period Td may be selected to be long enough to allowtemperature sensor circuit 2310 to detect the temperature range upperlimit value and/or temperature range lower limit value for eachtemperature range.

At time T1, the temperature of semiconductor device 2300 can reach thetemperature range upper limit value 2006. However, at this time,selection signal ISEL may be at a logic low level and temperature sensorcircuit 2310 (FIG. 24) may be enabled to detect the temperature rangelower limit value. In particular, with selection signal ISEL at a logiclow level, n-channel IGFET N2400 in temperature sensing portion 2410 maybe turned off. In this way, resistor R2420 may be included in the seriesresistance path between node N24 and ground so that temperature sensingportion may be enabled to detect temperature range lower limit value2502. Also, with selection signal ISEL at a logic low level, decrementsignal output portion 2430 may be enabled and increment signal outputportion 2420 may be disabled.

In this way, at time T1, temperature sensing circuit 2310 may not detectthe temperature of semiconductor device 2300 reaching the temperaturerange upper limit value 2006.

At time T2, selection signal ISEL may transition to a logic high level.With selection signal ISEL at a logic high level, n-channel IGFET N2400in temperature sensing portion 2410 may be turned on to provide a shuntfor resistor R2420. In this way, resistor R2420 may not be included inthe series resistance path between node N24 and ground so thattemperature sensing portion may be enabled to detect temperature rangeupper limit value 2506. Also, with selection signal ISEL at a logic highlevel, decrement signal output portion 2430 may be disabled andincrement signal output portion 2420 may be enabled. Thus, at time T2,temperature sensor circuit 2410 may provide an increment signal INC thattransitions from a low logic level to a high logic level. Count valueCNT[5:1] may be incremented in response to increment signal INC toprovide a count value CNT[5:1] having a value of “10001”. Counttransition signal CTD may detect a transition in the least significantbit CNT[1] of count value CNT[5:1] to provide a high going pulse. Readsignal READ (not shown) may be generated in response to count transitionsignal. In this way, performance parameters PP[m:1] may be provided.Load signal LOAD (not shown) may be generated in response to read signalREAD and performance parameter PP[m:1] may be latched to provide latchedperformance parameters PPL[5:1].

At this time latched performance parameters PPL[m:1] may have a value(shown as PPL-W34) for operating within temperature range W34.Temperature range W34 may have a temperature range lower limit value2504 and a temperature range upper limit value 2510. The temperaturerange lower limit value 2504 of temperature range W34 may be at a lowertemperature than the temperature range upper limit value 2506 oftemperature range W33. In this way, temperature ranges (W33 and W34) mayoverlap. The temperature range lower limit value 2508 of temperaturerange W35 may be at a lower temperature than the temperature range upperlimit value 2510 of temperature range W34. In this way, temperatureranges (W34 and W35) may overlap.

At time T3, the temperature of semiconductor device 2300 can reach thetemperature range lower limit value 2504. Because at this time,selection signal ISEL has a logic low level, temperature sensor circuit2310 (FIG. 24) may be enabled to detect the temperature range lowerlimit value as described above. Thus, temperature sensor circuit 2310may provide a decrement signal DEC that transitions from a low logiclevel to a high logic level. Count value CNT[5:1] may be decremented inresponse to decrement signal DEC to provide a count value CNT[5:1]having a value of “10000”. Count transition signal CTD may detect atransition in the least significant bit CNT[1] of count value CNT[5:1]to provide a high going pulse. Read signal READ (not shown) may begenerated in response to count transition signal. In this way,performance parameters PP[m:1] may be provided. Load signal LOAD (notshown) may be generated in response to read signal READ and performanceparameter PP[m:1] may be latched to provide latched performanceparameters PPL[5:1].

At this time, latched performance parameters PPL[m:1] may have a value(shown as PPL-W33) for operating within temperature range W33.

Referring now to FIG. 26, a circuit schematic diagram of performanceparameter adjusted circuits according to an embodiment is set forth andgiven the general reference character 2600.

Performance parameter adjusted circuits 2600 may be used in asemiconductor device (such as semiconductor devices 100 and 2300) thathave sub-threshold voltage operating circuits and above sub-thresholdvoltage operating circuits. A sub-threshold voltage operating circuit isa circuit that operates at a power supply potential level below thethreshold voltages of the included transistors (i.e. IGFETs). An abovesub-threshold voltage operating circuit is a circuit that operates at apower supply potential level above the threshold voltages of theincluded transistors (i.e. IGFETs).

Performance parameter adjusted circuits 2600 can include abovesub-threshold voltage operating circuits 2610, sub-threshold voltageoperating circuits 2620, power supply generating circuits (2612 and2622), and back bias voltage generating circuits (2614, 2616, 2624, and2626).

Above sub-threshold voltage operating circuits 2610 can include circuitsthat are configured of p-channel IGFETs PNM and n-channel IGFETs NNM.P-channel IGFETs PNM may receive a back body bias Vbp1 and n-channelIGFETs NNM may receive a back body bias Vbn1. The circuits in abovesub-threshold voltage operating circuits 2610 may receive a power supplyVDD1.

Sub-threshold voltage operating circuits 2620 can include circuits thatare configured of p-channel IGFETs PSUB and n-channel IGFETs NSUB.P-channel IGFETs PSUB may receive a back body bias Vbp2 and n-channelIGFETs NSUB may receive a back body bias Vbn2. The circuits in abovesub-threshold voltage operating circuits 2610 may receive a power supplyVDD2.

Each of power supply generating circuits (2612 and 2622), and back biasvoltage generating circuits (2614, 2616, 2624, and 2626) may receive aunique plurality (subset) of latched performance parameters (PPL[m:1])as inputs and may adjust the potentials of their outputs in responsethereto.

Power supply generating circuit 2612 may receive a plurality of latchperformance parameters (PPL[m:1]) as inputs and may provide a powersupply VDD1 as an output. Power supply VDD1 may be used as a powersupply for above sub-threshold voltage operating circuits 2610. In thisway, the potential of power supply VDD1 may vary in response to atemperature range in which the semiconductor device is operating.

Back bias voltage generating circuit 2614 may receive a plurality oflatch performance parameters (PPL[m:1]) as inputs and may provide a backbody bias Vbp1 as an output. Back body bias Vbp1 may be used as backbody bias for p-channel IGFETs PNM in above sub-threshold voltageoperating circuits 2610. In this way, the potential of back body biasVbp1 may vary in response to a temperature range in which thesemiconductor device is operating.

Back bias voltage generating circuit 2616 may receive a plurality oflatch performance parameters (PPL[m:1]) as inputs and may provide a backbody bias Vbn1 as an output. Back body bias Vbn1 may be used as backbody bias for n-channel IGFETs NNM in above sub-threshold voltageoperating circuits 2610. In this way, the potential of back body biasVbn1 may vary in response to a temperature range in which thesemiconductor device is operating.

Power supply generating circuit 2622 may receive a plurality of latchperformance parameters (PPL[m:1]) as inputs and may provide a powersupply VDD2 as an output. Power supply VDD2 may be used as a powersupply for sub-threshold voltage operating circuits 2620. In this way,the potential of power supply VDD2 may vary in response to a temperaturerange in which the semiconductor device is operating.

Back bias voltage generating circuit 2624 may receive a plurality oflatch performance parameters (PPL[m:1]) as inputs and may provide a backbody bias Vbp2 as an output. Back body bias Vbp2 may be used as backbody bias for p-channel IGFETs PSUB in sub-threshold voltage operatingcircuits 2620. In this way, the potential of back body bias Vbp2 mayvary in response to a temperature range in which the semiconductordevice is operating.

Back bias voltage generating circuit 2626 may receive a plurality oflatch performance parameters (PPL[m:1]) as inputs and may provide a backbody bias Vbn2 as an output. Back body bias Vbn2 may be used as backbody bias for n-channel IGFETs NSUB in sub-threshold voltage operatingcircuits 2620. In this way, the potential of back body bias Vbn2 mayvary in response to a temperature range in which the semiconductordevice is operating.

As described above, performance parameter adjusted circuits 2600 in asemiconductor device (100 and 2300) may have tight control over backbody biases (Vbp1, Vbn1, Vbp2, and Vbn2) and power supply voltages (VDD1and VDD2) to control threshold voltages and power supply voltages ofoperational circuits for both above sub-threshold voltage operatingcircuits 2610 and sub-threshold operating circuits 2620 in a pluralityof temperature ranges (such as temperature ranges (W1 to W2 ² shown inFIG. 16) so that speed and power consumption may be improved withoutdesigning for margins at extreme corners.

A temperature circuit may include, for example, temperature sensorcircuits (120 and 140) and/or temperature sensor circuit 2310.

A temperature circuit can provide a plurality of temperature ranges,each temperature range having a temperature range upper limit value anda temperature range lower limit value, with adjacent ones of theplurality of temperature ranges overlap. The temperature ranges may beutilized to provide performance parameters to performance parameteradjustable circuits to provide improved operating performance of thedevice over a wide range of temperatures.

Semiconductor device (100 and 2300) can be a dynamic random accessmemory (DRAM), static random access memory (SRAM), non-volatile memory(such as a FLASH memory device using floating gate memory cells or phasechange RAM using programmable resistive devices), processor, or generalsemiconductor device, as just a few examples.

Other electrical apparatus other than semiconductor devices may benefitfrom the invention.

While various particular embodiments set forth herein have beendescribed in detail, the present invention could be subject to variouschanges, substitutions, and alterations without departing from thespirit and scope of the invention. Accordingly, the present invention isintended to be limited only as defined by the appended claims.

What is claimed is:
 1. A device, comprising: a first temperature sensorcircuit setting a temperature range upper limit value, the firsttemperature sensor circuit provides a first direction output signals,the first direction output signal having a logic level transition inresponse to a temperature of the device reaching about the temperaturerange upper limit value; a second temperature sensor circuit setting atemperature range lower limit value, the second temperature sensorcircuit provides a second direction output signal, the second directionoutput signal having a logic level transition in response to thetemperature of the device reaching about the temperature range lowerlimit value; and a single counter circuit coupled to receive the firstdirection output signal and the second direction output signal andprovide a count value, the counter circuit incrementally changes thecount value by an incremental amount in a first direction in response tothe first direction output signal and incrementally changes the countvalue by the incremental amount in a second direction in response to thesecond direction output signal, wherein: the temperature range upperlimit value and the temperature range lower limit value changes inresponse to the incremental change in the count value.
 2. The device ofclaim 1, further including: the first temperature sensor circuit iscoupled to receive the count value, the count value sets the temperaturerange upper limit value.
 3. The device of claim 2, wherein: the secondtemperature sensor circuit is coupled to receive the count value, thecount value sets the temperature range lower limit value.
 4. The deviceof claim 1, further including: a count limit detector coupled to receivethe count value and provide a first count limit signal.
 5. The device ofclaim 4, wherein: the first temperature sensor circuit is coupled toreceive the first count limit signal, the first temperature sensorcircuit is disabled in response to the first count limit signal.
 6. Thedevice of claim 5, further including: the first temperature sensorcircuit includes a first temperature sensing portion coupled to receivethe count value and provide a first temperature detect signal; and afirst output portion coupled to receive the first temperature detectsignal and the first count limit signal and provide the first directionoutput signal wherein the first output portion is disabled in responseto the first count limit signal.
 7. The device, of claim 6, wherein: thecount limit detector provides a second count limit signal.
 8. The deviceof claim 7, wherein: the second temperature sensor circuit is coupled toreceive the second count limit signal, the second temperature sensorcircuit is disabled in response to the second count limit signal.
 9. Thedevice of claim 8, further including: the second temperature sensorcircuit includes a second temperature sensing portion coupled to receivethe count value and provide a second temperature detect signal; and asecond output portion coupled to receive the second temperature detectsignal and the second count limit signal and provide the seconddirection output signal wherein the second output portion is disabled inresponse to the second count limit signal.
 10. The device of claim 1,further including: a count transition detector coupled to receive aleast significant bit of the count value and provide a count transitionpulse signal in response to a logic transition of the least significantbit of the count value.
 11. The device of claim 10, further including:the first temperature sensor circuit is coupled to receive the counttransition pulse signal.
 12. The device, of claim 11, further including:the first temperature sensor circuit includes a first temperaturesensing portion coupled to receive the count value and provide a firsttemperature detect signal; and a first output portion coupled to receivethe first temperature detect signal and the count transition pulsesignal and provide the first direction output signal wherein the firstoutput portion is disabled in response to the count transition pulsesignal.
 13. The device of claim 12, wherein the second temperaturesensor circuit is coupled to receive the count transition pulse signal.14. The device of claim 13, further including: the second temperaturesensor circuit includes a second temperature sensing portion coupled toreceive the count value and provide a second temperature detect signal;and a second output portion coupled to receive the second temperaturedetect signal and the count transition pulse signal and provide thesecond direction output signal wherein the second output portion isdisabled in response to the count transition pulse signal.
 15. Thedevice of claim 1, wherein: the first temperature sensor circuitincludes a first variable resistor coupled to receive the count value,the first variable resistor includes a first resistance value thatchanges in response to the incremental change of the count value. 16.The device of claim 15, wherein: the second temperature sensor circuitincludes a second variable resistor coupled to receive the count value,the second variable resistor includes a second resistance value thatchanges in response to the incremental change of the count value. 17.The device of claim 1, further including: a performance parameter tablecoupled to receive the count value, the performance parameter tableprovides performance parameters addressed by the count value.
 18. Thedevice of claim 17, further including: performance parameter adjustedcircuits coupled to receive the performance parameters, performanceparameter adjusted circuits have operational aspects adjusted inresponse to the values of the performance parameters.
 19. The device ofclaim 1, wherein: the device is a semiconductor device.